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Search: id:A074312
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| A074312 |
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Product of the digits of n equals the number of divisors of n. |
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+0
2
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| 1, 2, 14, 22, 24, 32, 42, 116, 122, 126, 141, 211, 221, 222, 411, 512, 1114, 1118, 1128, 1132, 1141, 1144, 1218, 1222, 1242, 1314, 1332, 1411, 1611, 1612, 2111, 2114, 2132, 2214, 2232, 2312, 2511, 3114, 3211, 3212, 4116, 4131, 4312, 6112, 8211
(list; graph; listen)
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OFFSET
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1,2
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EXAMPLE
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24 is a member as the product of the digits of 24 is 2*4 = 8 and the number of divisors = 8.
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MAPLE
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with(numtheory):l := 1:a[1] := 1:for n from 2 to 10000 do d := convert(n, base, 10): if(product(d[i], i=1..nops(d))=tau(n)) then l := l+1:a[l] := n:fi:od:seq(a[i], i=1..l); (from Sascha Kurz)
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MATHEMATICA
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Select[Range[10^4], Apply[Times, IntegerDigits[ # ]] == DivisorSigma[0, # ] &]
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CROSSREFS
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Cf. A057531.
Sequence in context: A086263 A073143 A066613 this_sequence A061426 A069512 A116639
Adjacent sequences: A074309 A074310 A074311 this_sequence A074313 A074314 A074315
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KEYWORD
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base,easy,nonn
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AUTHOR
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Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Sep 22 2002
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