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 A004624 Divisible only by primes congruent to 6 mod 7. 1
 1, 13, 41, 83, 97, 139, 167, 169, 181, 223, 251, 293, 307, 349, 419, 433, 461, 503, 533, 587, 601, 643, 727, 769, 797, 811, 839, 853, 881, 937, 1021, 1049, 1063, 1079, 1091, 1217, 1231, 1259, 1261, 1301, 1399, 1427, 1483, 1511, 1553, 1567, 1609, 1637, 1681 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 MATHEMATICA ok[1]=True; ok[n_]:=And@@(Mod[#, 7]==6&)/@FactorInteger[n][[All, 1]]; Select[Range[5000], ok] (* Vincenzo Librandi, Aug 20 2012 *) PROG (Magma) [n: n in [1..2000] | forall{d: d in PrimeDivisors(n) | d mod 7 eq 6}]; // Vincenzo Librandi, Aug 20 2012 CROSSREFS Sequence in context: A031373 A043162 A043942 * A045473 A102083 A139866 Adjacent sequences: A004621 A004622 A004623 * A004625 A004626 A004627 KEYWORD nonn AUTHOR N. J. A. Sloane EXTENSIONS Offset changed from 0 to 1 by Vincenzo Librandi, Aug 20 2012 STATUS approved

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Last modified December 7 11:26 EST 2023. Contains 367650 sequences. (Running on oeis4.)