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.

A325451 Numbers k such that sum of digits (k) and sum of digits (k^2) is 10.

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%I A325451 #15 Sep 08 2022 08:46:24
%S A325451 19,46,55,145,190,361,451,460,550,1450,1900,3610,4510,4600,5500,14500,
%T A325451 19000,20251,36100,45100,46000,55000,145000,190000,202510,361000,
%U A325451 451000,460000,550000,1450000,1900000,2025100,3610000,4510000,4600000,5500000,14500000
%N A325451 Numbers k such that sum of digits (k) and sum of digits (k^2) is 10.
%C A325451 Subsequence of A058369 (k and k^2 have same digit sum).
%C A325451 A007953(A058369(n)) begins with 1, 9, 1, 9, 10, 9, 10, 10, 9, 18, ...: the 1's come from A011557, the 9's come from A325450, and the 10's come from this sequence.
%e A325451 a(4) = 145 because 1+4+5 = 10, 145^2 = 21025, and 2+1+0+2+5 = 10.
%t A325451 Select[Range[2 10^7], Total[IntegerDigits[#]]==10 && Total[IntegerDigits[#^2]]==10 &]
%o A325451 (Magma) [n: n in [1..2*10^7] | &+Intseq(n^2) eq 10  and &+Intseq(n) eq 10];
%Y A325451 Cf. A004159, A007953, A058369, A325450.
%K A325451 nonn,base
%O A325451 1,1
%A A325451 _Vincenzo Librandi_, May 10 2019