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.

A225722 Numbers divisible by their last digit cubed, excluding those whose last digit is 1.

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%I A225722 #18 Aug 08 2023 03:22:01
%S A225722 32,64,72,112,125,152,192,216,232,243,272,312,352,375,384,392,432,472,
%T A225722 512,513,552,592,625,632,672,704,712,729,752,783,792,832,872,875,912,
%U A225722 952,992,1024,1032,1053,1072,1112,1125,1152,1192,1232,1272,1296,1312,1323
%N A225722 Numbers divisible by their last digit cubed, excluding those whose last digit is 1.
%C A225722 a(n) ~ n. For 69 < n < 10000, the formula 26.61*n - 2.76 provides an estimate of a(n) to within 1%.
%C A225722 The asymptotic density of this sequence is 601296607/16003008000 = 0.037573... . Therefore, contrary to the above comment, a(n) ~ c*n where c = 16003008000/601296607 = 26.614166... . - _Amiram Eldar_, Aug 08 2023
%H A225722 Christian N. K. Anderson, <a href="/A225722/b225722.txt">Table of n, a(n) for n = 1..10000</a>
%e A225722 a(5) = 125 is an example because its last digit is 5, and 5^3 = 125, and 125 is divisible by 125.
%t A225722 dldcQ[n_]:=Module[{ld=Last[IntegerDigits[n]]},ld>1&&Divisible[n,ld^3]]; Select[Range[1500],dldcQ] (* _Harvey P. Dale_, Aug 15 2014 *)
%o A225722 (R)
%o A225722 which(sapply(1:1000,function(x) x%%10>1 & (v=x/(x%%10)^3)==as.integer(v) ))
%Y A225722 Subsequence of A225297.
%Y A225722 Cf. A221651, A225296, A132359, A034709, A034837, A005349, A007602, A034838.
%K A225722 nonn,base
%O A225722 1,1
%A A225722 _Kevin L. Schwartz_ and _Christian N. K. Anderson_, May 13 2013