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 A062670 Composite and every divisor (except 1) contains the digit 4. 18
 1849, 6407, 14227, 14309, 14921, 16403, 16441, 17243, 18409, 18847, 19049, 19147, 20459, 20941, 21457, 21479, 21949, 22427, 23453, 25427, 27649, 30409, 30463, 31949, 34921, 40463, 40721, 43009, 44227, 44509, 45107, 49303, 58343, 59491 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 EXAMPLE 1849 has divisors 1, 43 and 1849, all of which contain the digit 4. MATHEMATICA fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 59500], !PrimeQ[#] && fQ[#, 4] &] (* Robert G. Wilson v, Jun 11 2014 *) d4Q[n_]:=CompositeQ[n]&&AllTrue[Rest[Divisors[n]], DigitCount[#, 10, 4]>0&]; Select[Range[ 60000], d4Q] (* Harvey P. Dale, Jun 20 2023 *) CROSSREFS Cf. A062653, A062664, A062667, A062668, A062669, A062671, A062672, A062673, A062674, A062675, A062676, A062677, A062678, A062679, A062680. Sequence in context: A237892 A326318 A115719 * A206468 A031764 A031674 Adjacent sequences: A062667 A062668 A062669 * A062671 A062672 A062673 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 November 28 04:05 EST 2023. Contains 367394 sequences. (Running on oeis4.)