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 A164937 Near-repdigit primes. 8
 101, 113, 131, 151, 181, 191, 199, 211, 223, 227, 229, 233, 277, 311, 313, 331, 337, 353, 373, 383, 433, 443, 449, 499, 557, 577, 599, 661, 677, 727, 733, 757, 773, 787, 797, 811, 877, 881, 883, 887, 911, 919, 929, 977, 991, 997, 1117, 1151, 1171, 1181, 1511 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert G. Wilson v, Table of n, a(n) for n = 1..22172 (first 5000 terms from Arkadiusz Wesolowski) Chris Caldwell, The Top 20 Near-repdigit Primes Chris Caldwell, The Prime Glossary, Near-repdigit prime Brady Haran and Simon Pampena, Glitch Primes and Cyclops Numbers, Numberphile video (2015) MATHEMATICA lst = {}; Do[If[PrimeQ[n] && SortBy[Tally[IntegerDigits[n]], Last][[-1, -1]] == IntegerLength[n] - 1, AppendTo[lst, n]], {n, 101, 10^3}]; lst (* Arkadiusz Wesolowski, Sep 18 2011 *) lst = {}; Do[r = (10^n - 1)/9; Do[AppendTo[lst, DeleteCases[Select[FromDigits[Permutations[Append[IntegerDigits[a*r], d]]], PrimeQ], r | 2 | 3 | 5 | 7]], {a, 9}, {d, 0, 9}], {n, 2, 6}]; Sort[Flatten[lst]] (* Arkadiusz Wesolowski, Sep 22 2011 *) PROG (Python) from sympy import isprime from itertools import count, islice def agen(): # generator of terms for d in count(3): ds = set() for end in "1379": ds.update(int(c*(d-1) + end) for c in "123456789" if c != end) for diff in "0123456789": if end == diff: continue cands = (end*i + diff + end*(d-1-i) for i in range(d-1)) ds.update(int(t) for t in cands if t[0] != "0") yield from sorted(t for t in ds if isprime(t)) print(list(islice(agen(), 52))) # Michael S. Branicky, May 17 2022 CROSSREFS Cf. A105992, A105975, A105976, A105977, A105978, A105979, A105980, A105981, A105982, A065074. Sequence in context: A248533 A069691 A084414 * A105992 A038370 A084430 Adjacent sequences: A164934 A164935 A164936 * A164938 A164939 A164940 KEYWORD nonn,base AUTHOR G. L. Honaker, Jr., Aug 31 2009 EXTENSIONS Three more terms from Lekraj Beedassy, Dec 06 2009 STATUS approved

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Last modified December 4 10:52 EST 2023. Contains 367560 sequences. (Running on oeis4.)