In recreational mathematics, a repunit is a number like 11, 111, or 1111 that contains only the digit 1 — a more specific type of repdigit. The term stands...
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This is a list of repunit primes in various bases. Base-2 repunit primes are called Mersenne primes. The first few base-3 repunit primes are 13, 1093...
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Repdigit (section Primes and repunits)
repdigits are palindromic numbers and are multiples of repunits. Other well-known repdigits include the repunit primes and in particular the Mersenne primes (which...
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Mersenne prime (section Repunit primes)
11111111111111111111111, ... (sequence A004022 in the OEIS). These primes are called repunit primes. Another example is when we take b = −12, we get n values of: 2...
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Numerical digit (section Repunits and repdigits)
faulty. Repunits are integers that are represented with only the digit 1. For example, 1111 (one thousand, one hundred and eleven) is a repunit. Repdigits...
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199933, 1111111111111111111, 11111111111111111111111 (OEIS: A016114) All repunit primes are circular. A cluster prime is a prime p such that every even...
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051 = fifth Keith prime 1,089,270 = harmonic divisor number 1,111,111 = repunit 1,112,083 = logarithmic number 1,129,30832 + 1 is prime 1,136,689 = Pell...
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squaring the square). 111 is R 3 {\displaystyle R_{3}} or the second repunit in decimal, a number like 11, 111, or 1111 that consists of repeated units...
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primes, but later they were also called absolute primes. In base 2, only repunits can be permutable primes, because any 0 permuted to the ones place results...
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Sierpinski problem 55555 = repdigit 55860 = harmonic divisor number 55987 = repunit prime in base 6 56011 = Wedderburn-Etherington number 56092 = the number...
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is a square (11 times 11) the sum of the powers of 3 from 0 to 4, so a repunit in ternary. Furthermore, 121 is the only square of the form 1 + p + p 2...
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Eisenstein integers. 271 is the largest prime factor of the five-digit repunit 11111, and the largest prime number for which the decimal period of its...
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641, 2137, 3011, 268207, ... (sequence A001562 in the OEIS). See Repunit#Repunit primes for the list of the generalized Wagstaff primes base b {\displaystyle...
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in decimal R 19 {\displaystyle R_{19}} is also the second to be a prime repunit (after R 2 {\displaystyle R_{2}} ), followed by R 23 {\displaystyle R_{23}}...
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2002 TK102 Repeated 1 1 Ceres 11 Parthenope 111 Ate 1111 Reinmuthia 11111 Repunit (111111) 2001 VO84 Repeated 2 2 Pallas 22 Kalliope 222 Lucia 2222 Lermontov...
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divisible by the sum of its digits, making it a Harshad number. The smallest repunit probable prime in base 152 was found in June 2015, it has 589570 digits...
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a repunit, a number consisting only of n ones (in base 10). There are no other circular primes up to 1025. The only other known examples are repunit primes...
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number. 317 is the exponent (and number of ones) in the fourth base-10 repunit prime. 319 = 11 × 29. 319 is the sum of three consecutive primes (103 +...
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integer ≥ 2 for z, this sum becomes a base z repunit. Thus a necessary (but not sufficient) condition for a repunit to be prime is that its length be prime...
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number of partially ordered set with 12 unlabeled elements 1,111,111,111 : repunit, also a special number relating to the passing of Unix time. 1,129,760...
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972,410,221 = number of trees with 32 unlabeled nodes 111,111,111,111 = repunit 118,587,876,497 = 49133 = 179 127,004,500,762 = number of parallelogram...
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1038232 = 22093 = 476 11,019,960,576 = 1049762 = 3244 = 188 11,111,111,111 = repunit 11,123,060,678 = number of free 21-ominoes 11,874,568,703 = number of partitions...
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Automorphic Trimorphic Digit-composition related Palindromic Pandigital Repdigit Repunit Self-descriptive Smarandache–Wellin Undulating Digit-permutation related...
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22222 22447 = cuban prime 22527 = Woodall number: 11 × 211 − 1 22621 = repunit prime in base 12 22699 = one of five remaining Seventeen or Bust numbers...
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concept, professional mathematicians generally are not. Like the concept of repunits and palindromic numbers, the concept of strobogrammatic numbers is base-dependent...
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Automorphic Trimorphic Digit-composition related Palindromic Pandigital Repdigit Repunit Self-descriptive Smarandache–Wellin Undulating Digit-permutation related...
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with 10,000 or more decimal digits.[citation needed] He is the author of Repunits and Repetends. Between 1940 and 1973 Yates worked a number of different...
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power and not of the form −4k4 for integer k, are there infinitely many repunit primes to base b? For any given integers k ≥ 1 , b ≥ 2 , c ≠ 0 {\displaystyle...
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413,504 = 147 107,890,609 = Wedderburn-Etherington number 111,111,111 = repunit, square root of 12345678987654321 111,111,113 = Chen prime, Sophie Germain...
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with index 2. a palindromic number in bases 7 (3137) and 12 (11112). a repunit in base 12, so it is a unique prime in the same base a prime whose digits...
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