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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.

A259489 Numbers n such that n plus the cube of sum of digits of n is a perfect square.

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%I A259489 #10 Sep 08 2022 08:46:13
%S A259489 17,38,131,171,360,392,500,512,605,729,863,1031,1035,1481,1737,1994,
%T A259489 2156,2268,2483,2513,2520,2732,2817,3011,3240,3384,3449,3710,3881,
%U A259489 3923,4032,4100,4112,4145,4572,5193,5456,5598,5720,5832,5903,5924,7164,7388,7625,7631
%N A259489 Numbers n such that n plus the cube of sum of digits of n is a perfect square.
%C A259489 All the terms are congruent to 2 or 0 (mod 3).
%H A259489 K. D. Bajpai, <a href="/A259489/b259489.txt">Table of n, a(n) for n = 1..10000</a>
%e A259489 a(3) = 131: 131 + (1 + 3 + 1)^3 = 256 = 16^2.
%e A259489 a(4) = 171: 171 + (1 + 7 + 1)^3 = 900 = 30^2.
%t A259489 Select[Range[50000], IntegerQ[Sqrt[# +Plus@@(IntegerDigits[#])^3]]&]
%o A259489 (PARI) for(n = 1, 10^5, if(issquare(sumdigits(n)^3 + n), print1(n, ", ")))
%o A259489 (Magma) [ n: n in [1..10^4] |  IsSquare(&+Intseq(n)^3 + n) ] ;
%Y A259489 Cf. A007494, A052034, A061309, A091365, A091366.
%K A259489 nonn,base
%O A259489 1,1
%A A259489 _K. D. Bajpai_, Jun 28 2015