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%I #17 Jan 04 2024 15:36:26
%S 3,6,9,12,15,18,21,30,39,45,48,51,60,90,102,105,111,120,150,180,201,
%T 210,249,300,318,321,348,351,390,450,480,501,510,549,600,900,1002,
%U 1005,1011,1020,1050,1101,1110,1149,1200,1500,1761,1800,2001,2010,2100,2490
%N Numbers n such that sum of digits on n^2 is 9.
%C Subsequence of A008585.
%H Robert Israel, <a href="/A262712/b262712.txt">Table of n, a(n) for n = 1..1000</a>
%e 6 is in sequence because 6^2 = 36 and 3+6 = 9.
%p filter:= proc(n) convert(convert(n^2,base,10),`+`) = 9 end proc:select(filter, [$1..10^5]); # _Robert Israel_, Jan 04 2024
%t Select[Range[10^5], Total[IntegerDigits[#^2]] == 9 &]
%o (Magma) [n: n in [1..2*10^4] | &+Intseq(n^2) eq 9 ];
%o (PARI) for(n=1, 1e8, if (sumdigits(n^2) == 9, print1(n", "))) \\ _Altug Alkan_, Sep 28 2015
%Y Cf. similar sequences listed in A262711.
%Y Cf. A004159, A008585, A061910.
%K nonn,base
%O 1,1
%A _Vincenzo Librandi_, Sep 28 2015
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