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.

A352463 Numbers k with the property that the product of the digits of k starts k.

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%I A352463 #12 Mar 18 2022 13:07:57
%S A352463 1,2,3,4,5,6,7,8,9,11,21,31,41,51,61,71,81,91,111,126,153,211,243,311,
%T A352463 362,411,511,611,711,811,911,1111,1216,1223,1232,1261,1288,1359,1449,
%U A352463 1513,1531,1755,2111,2413,2431,3111,3612,3621,3844,4111,5111,6111,6728,7111,7357,8111,9111,11111,11278,11287
%N A352463 Numbers k with the property that the product of the digits of k starts k.
%e A352463 a(10) = 11 starts with 1, which is the product 1*1;
%e A352463 a(20) = 126 starts with 12, which is the product 1*2*6;
%e A352463 a(42) = 1755 starts with 175, which is the product ; 1*7*5*5; etc.
%t A352463 q[n_] := Module[{d = IntegerDigits[n], p, dp, ndp}, p = Times @@ d; dp = IntegerDigits[p]; ndp = Length[dp]; dp == d[[1 ;; ndp]]]; Select[Range[12000], q] (* _Amiram Eldar_, Mar 18 2022 *)
%o A352463 (Python)
%o A352463 from math import prod
%o A352463 def ok(n): s = str(n); return s.startswith(str(prod(map(int, s))))
%o A352463 print([k for k in range(1, 12000) if ok(k)]) # _Michael S. Branicky_, Mar 17 2022
%Y A352463 Cf. A203565, A352461, A352464.
%K A352463 base,nonn
%O A352463 1,2
%A A352463 _Eric Angelini_ and _Carole Dubois_, Mar 17 2022