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A062653
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Every divisor (except 1) contains the digit 2.
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17
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2, 23, 29, 127, 211, 223, 227, 229, 233, 239, 241, 251, 254, 257, 263, 269, 271, 277, 281, 283, 293, 421, 422, 482, 502, 521, 523, 526, 529, 542, 562, 727, 821, 823, 827, 829, 842, 929, 1021, 1042, 1123, 1129, 1201, 1213, 1217, 1223, 1229, 1231, 1237
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OFFSET
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1,1
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LINKS
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EXAMPLE
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254 has divisors 1, 2, 127 and 254, all of which contain the digit 2.
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MATHEMATICA
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fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 1300], fQ[#, 2] &] (* Robert G. Wilson v, Jun 11 2014 *)
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PROG
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(Magma) [k:k in [2..1300]| forall{d:d in Set(Divisors(k)) diff {1}| 2 in Intseq(d)}]; // Marius A. Burtea, Nov 07 2019
(PARI) has2(n)=if(n==1, return(1)); !!setsearch(Set(digits(n)), 2)
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CROSSREFS
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Cf. A062664, A062667, A062668, A062669, A062670, A062671, A062672, A062673, A062674, A062675, A062676, A062677, A062678, A062679, A062680.
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KEYWORD
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base,easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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