cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A316147 Numbers, with digits in nondecreasing order, whose product of digits equals the number of digits times the sum of digits.

This page as a plain text file.
%I A316147 #18 Aug 12 2021 12:45:36
%S A316147 0,1,2,3,4,5,6,7,8,9,36,44,159,167,235,333,1247,1344,2226,11259,11355,
%T A316147 111279,111366,112239,112246,112335,1111377,1111457,1112337,11111388,
%U A316147 11112267,11113344,11122236,11222224,111111399,111111559,111111666,111112269
%N A316147 Numbers, with digits in nondecreasing order, whose product of digits equals the number of digits times the sum of digits.
%C A316147 This sequence can be used to find terms of A064154 by permuting digits of terms of this sequence.
%t A316147 Union@ Flatten@ Reap[ Sow[0]; Do[ If[ FactorInteger[ nd s ][[-1, 1]] <= 7, Sow[ FromDigits /@ Reverse /@ Select[ IntegerPartitions[s, {nd}, Range[9]], Times @@ # == Length[#] Plus @@ # &]]], {nd, 18}, {s, 9 nd}]][[2, 1]] (* terms < 10^18, _Giovanni Resta_, Jul 18 2018 *)
%t A316147 dnoQ[n_]:=Module[{idn=IntegerDigits[n]},Min[Differences[idn]]>=0 && Times@@idn==Length[idn]Total[idn]]; Select[Range[0, 111112300],dnoQ] (* _Harvey P. Dale_, Aug 12 2021 *)
%o A316147 (PARI) is(n) = my(d = digits(n)); vecsort(d) == d && prod(i=1, #d, d[i]) == #d * vecsum(d) \\ _David A. Corneth_, Jul 18 2018
%Y A316147 Cf. A064154.
%K A316147 nonn,base,easy
%O A316147 1,3
%A A316147 _David A. Corneth_, Jun 25 2018