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%I #21 Sep 08 2022 08:46:14
%S 4,5,32,40,49,50,149,320,400,490,500,1049,1490,3200,4000,4900,5000,
%T 10490,14900,32000,40000,49000,50000,104900,149000,320000,400000,
%U 490000,500000,1049000,1490000,3200000,4000000,4900000,5000000,10490000,14900000
%N Numbers n such that sum of digits of n^2 is 7.
%C Subsequence of A156638. [_Bruno Berselli_, Sep 28 2015]
%e 4 is in sequence because 4^2 = 16 and 1+6 = 7.
%t Select[Range[10^7], Total[IntegerDigits[#^2]] == 7 &]
%o (Magma) [n: n in [1..2*10^7] | &+Intseq(n^2) eq 7];
%o (PARI) for(n=1, 1e8, if (sumdigits(n^2) == 7, print1(n", "))) \\ _Altug Alkan_, Sep 28 2015
%Y Cf. sum of digits of n^2 is k: A052216 (k=4), this sequence (k=7), A262712 (k=9), A262713 (k=10).
%Y Cf. A004159, A061910, A156638.
%K nonn,base
%O 1,1
%A _Vincenzo Librandi_, Sep 28 2015
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