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.

A062034 Positive numbers whose product of digits is twice the sum of the digits.

This page as a plain text file.
%I A062034 #22 Dec 05 2024 14:45:41
%S A062034 36,44,63,138,145,154,183,224,242,318,381,415,422,451,514,541,813,831,
%T A062034 1146,1164,1225,1233,1252,1323,1332,1416,1461,1522,1614,1641,2125,
%U A062034 2133,2152,2215,2222,2251,2313,2331,2512,2521,3123,3132,3213,3231,3312,3321
%N A062034 Positive numbers whose product of digits is twice the sum of the digits.
%H A062034 Harry J. Smith, <a href="/A062034/b062034.txt">Table of n, a(n) for n = 1..500</a>
%e A062034 1225 belongs to the sequence as (1*2*2*5)/(1+2+2+5) =20/10 = 2.
%t A062034 Select[Range[4000],Times@@IntegerDigits[#]==2Total[IntegerDigits[#]]&] (* _Harvey P. Dale_, Dec 11 2016 *)
%o A062034 (PARI) isok(n) = my(d=digits(n)); vecprod(d)==2*vecsum(d) \\ _Mohammed Yaseen_, Jul 28 2022
%o A062034 (Python)
%o A062034 from math import prod
%o A062034 def ok(n): d = list(map(int, str(n))); return prod(d) == 2*sum(d)
%o A062034 print([k for k in range(1, 4000) if ok(k)]) # _Michael S. Branicky_, Jul 28 2022
%Y A062034 Cf. A011540, A034710, A062035, A062036, A062382, A062037, A062384, A062040, A062041, A062043, A062045.
%K A062034 nonn,base,easy
%O A062034 1,1
%A A062034 _Amarnath Murthy_, Jun 27 2001
%E A062034 Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jul 06 2001
%E A062034 Offset corrected by _Mohammed Yaseen_, Jul 28 2022