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A062649 Composite numbers with property that every divisor contains the digit 1. 1
121, 143, 169, 187, 221, 341, 361, 451, 671, 781, 961, 1037, 1111, 1133, 1159, 1177, 1199, 1207, 1243, 1271, 1313, 1331, 1339, 1349, 1391, 1397, 1417, 1441, 1469, 1507, 1529, 1573, 1639, 1651, 1661, 1681, 1703, 1717, 1727, 1751, 1781, 1793, 1807, 1819 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A002808 and A062634. - Michel Marcus, Sep 12 2013

LINKS

Table of n, a(n) for n=1..44.

EXAMPLE

143 has divisors 1, 11, 13 and 143, all of which contain the digit 1.

MATHEMATICA

fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 1850], !PrimeQ[#] && fQ[#, 1] &] (* Robert G. Wilson v, Jun 11 2014 *)

PROG

(PARI) lista(nn) = {forcomposite(n = 1, nn, ok = 1; fordiv(n, d, ok = ok && setsearch(Set(digits(d)), 1)); if (ok, print1(n, ", ")); ); } \\ Michel Marcus, Sep 12 2013

CROSSREFS

Sequence in context: A271630 A038511 A285784 * A206288 A287390 A258202

Adjacent sequences:  A062646 A062647 A062648 * A062650 A062651 A062652

KEYWORD

base,easy,nonn

AUTHOR

Erich Friedman, Jul 04 2001

STATUS

approved

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Last modified July 22 20:49 EDT 2019. Contains 325226 sequences. (Running on oeis4.)