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A062669 Every divisor (except 1) contains the digit 4. 2
41, 43, 47, 149, 241, 347, 349, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499, 541, 547, 641, 643, 647, 743, 941, 947, 1049, 1249, 1409, 1423, 1427, 1429, 1433, 1439, 1447, 1451, 1453, 1459, 1471, 1481, 1483, 1487 (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, 1500], fQ[#, 4] &] (* Robert G. Wilson v, Jun 11 2014 *)

PROG

(MAGMA) [k:k in [2..1500]| forall{d:d in Set(Divisors(k)) diff {1}| 4 in Intseq(d)}]; // Marius A. Burtea, Nov 07 2019

CROSSREFS

Cf. A062653, A062664, A062667, A062668, A062670, A062671, A062672, A062673, A062674, A062675, A062676, A062677, A062678, A062679, A062680.

Sequence in context: A154498 A223458 A243429 * A284290 A045710 A090152

Adjacent sequences:  A062666 A062667 A062668 * A062670 A062671 A062672

KEYWORD

base,easy,nonn,changed

AUTHOR

Erich Friedman, Jul 04 2001

EXTENSIONS

Offset corrected by Amiram Eldar, Nov 07 2019

STATUS

approved

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Last modified November 12 17:06 EST 2019. Contains 329058 sequences. (Running on oeis4.)