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.

A321771 Numbers whose digit product equals the number of their digits.

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%I A321771 #38 Nov 23 2018 03:52:39
%S A321771 1,12,21,113,131,311,1114,1122,1141,1212,1221,1411,2112,2121,2211,
%T A321771 4111,11115,11151,11511,15111,51111,111116,111123,111132,111161,
%U A321771 111213,111231,111312,111321,111611,112113,112131,112311,113112,113121,113211,116111,121113
%N A321771 Numbers whose digit product equals the number of their digits.
%C A321771 Idea is similar to A061384, which uses addition instead of multiplication.
%H A321771 Giovanni Resta, <a href="/A321771/b321771.txt">Table of n, a(n) for n = 1..10000</a>
%e A321771 12 has two digits, and their product is also 2, as 1*2=2.
%t A321771 Select[Range[1000000], Length[IntegerDigits[#]] == Times @@ IntegerDigits[#] &] (* _Amiram Eldar_, Nov 21 2018 *)
%o A321771 (PARI) isok(n) = my(d=digits(n)); vecprod(d) == #d; \\ _Michel Marcus_, Nov 22 2018
%Y A321771 Cf. A061384.
%Y A321771 Cf. A007954, A055642. Subsequence of A007602.
%Y A321771 Subsequence of A052382 (zeroless numbers).
%K A321771 nonn,base
%O A321771 1,2
%A A321771 _Ivan Stoykov_, Nov 21 2018
%E A321771 More terms from _Amiram Eldar_, Nov 21 2018