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 A074312 Numbers k such that the product of the digits of k equals the number of divisors of k. 3
 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; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Giovanni Resta, Table of n, a(n) for n = 1..10000 EXAMPLE 24 is a term as the product of the digits of 24 is 2*4 = 8 and the number of divisors = 8. MAPLE 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); # Sascha Kurz MATHEMATICA Select[Range[10^4], Apply[Times, IntegerDigits[ # ]] == DivisorSigma[0, # ] &] CROSSREFS Cf. A057531, A066613. Sequence in context: A335071 A073143 A066613 * A061426 A190045 A247035 Adjacent sequences: A074309 A074310 A074311 * A074313 A074314 A074315 KEYWORD base,easy,nonn AUTHOR Joseph L. Pe, Sep 22 2002 STATUS approved

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Last modified September 11 10:08 EDT 2024. Contains 375827 sequences. (Running on oeis4.)