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 A105992 Near-repunit primes. 16
 101, 113, 131, 151, 181, 191, 211, 311, 811, 911, 1117, 1151, 1171, 1181, 1511, 1811, 2111, 4111, 8111, 10111, 11113, 11117, 11119, 11131, 11161, 11171, 11311, 11411, 16111, 101111, 111119, 111121, 111191, 111211, 111611, 112111, 113111, 131111, 311111, 511111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS According to the prime glossary "a near-repunit prime is a prime all but one of whose digits are 1." This would also include {2, 3, 5, 7, 13, 17, 19, 31, 41, 61 and 71}, but this sequence only lists terms with more than two digits. - M. F. Hasler, Feb 10 2020 REFERENCES C. Caldwell and H. Dubner, "The near repunit primes 1(n-k-1)01(1k)," J. Recreational Math., 27 (1995) 35-41. Heleen, J. P., "More near-repunit primes 1(n-k-1)D(1)1(k), D=2,3, ..., 9," J. Recreational Math., 29:3 (1998) 190-195. LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 Chris Caldwell, The Top 20 Near-repdigit Primes Chris Caldwell, The Prime Glossary, Near-repunit prime EXAMPLE a(2)=113 is a term because 113 is a prime and all digits are 1 except one. MATHEMATICA lst = {}; Do[r = (10^n - 1)/9; Do[AppendTo[lst, DeleteCases[Select[FromDigits[Permutations[Append[IntegerDigits[r], d]]], PrimeQ], r]], {d, 0, 9}], {n, 2, 14}]; Sort[Flatten[lst]] (* Arkadiusz Wesolowski, Sep 20 2011 *) CROSSREFS Cf. A000042, A002275, A004022, A046053, A046413, A065074, A034093, A065083, A102782, A118505. Sequence in context: A069691 A084414 A164937 * A038370 A084430 A182693 Adjacent sequences: A105989 A105990 A105991 * A105993 A105994 A105995 KEYWORD base,nonn AUTHOR Shyam Sunder Gupta, Apr 29 2005 STATUS approved

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Last modified August 14 19:51 EDT 2024. Contains 375167 sequences. (Running on oeis4.)