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 A062676 Composite and every divisor (except 1) contains the digit 7. 18
 497, 679, 749, 799, 1207, 1379, 1739, 1799, 1897, 2479, 2627, 2701, 2779, 3337, 3713, 3997, 4607, 4709, 4711, 4739, 4757, 4907, 5173, 5257, 5327, 5579, 5729, 5767, 5789, 6179, 6749, 6769, 6797, 6887, 6979, 7081, 7169, 7289, 7379, 7597, 7609, 7663 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 EXAMPLE 799 has divisors 17, 47 and 799, all of which contain the digit 7. MATHEMATICA fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 7670], !PrimeQ[#] && fQ[#, 7] &] (* Robert G. Wilson v, Jun 11 2014 *) PROG (MAGMA) [k:k in [2..8000]|  not IsPrime(k) and forall{d:d in Set(Divisors(k)) diff {1}| 7 in Intseq(d)}]; // Marius A. Burtea, Nov 07 2019 CROSSREFS Cf. A062653, A062664, A062667, A062668, A062669, A062670, A062671, A062672, A062673, A062674, A062675, A062677, A062678, A062679, A062680. Sequence in context: A088845 A013685 A108157 * A097785 A145922 A145981 Adjacent sequences:  A062673 A062674 A062675 * A062677 A062678 A062679 KEYWORD base,easy,nonn AUTHOR Erich Friedman, Jul 04 2001 EXTENSIONS Offset corrected by Amiram Eldar, Nov 07 2019 STATUS approved

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Last modified May 14 17:44 EDT 2021. Contains 343900 sequences. (Running on oeis4.)