A062675 Every divisor (except 1) contains the digit 7.

7, 17, 37, 47, 67, 71, 73, 79, 97, 107, 127, 137, 157, 167, 173, 179, 197, 227, 257, 271, 277, 307, 317, 337, 347, 367, 373, 379, 397, 457, 467, 479, 487, 497, 547, 557, 571, 577, 587, 607, 617, 647, 673, 677, 679, 701, 709, 719, 727, 733, 739, 743, 749, 751

Offset: 1

Author

Erich Friedman, Jul 04 2001

Keywords

• nonn
• base
• easy

Examples

			799 has divisors 17, 47 and 799, all of which contain the digit 7.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A062653, A062664, A062667, A062668, A062669, A062670, A062671, A062672, A062673, A062674, A062676, A062677, A062678, A062679, A062680.

Programs

Magma

[k:k in [2..800]| forall{d:d in Set(Divisors(k)) diff {1}| 7 in Intseq(d)}];// Marius A. Burtea, Nov 07 2019

Mathematica

fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 760], fQ[#, 7] &]  (* Robert G. Wilson v, Jun 11 2014 *)