A262712 Numbers n such that sum of digits on n^2 is 9.

3, 6, 9, 12, 15, 18, 21, 30, 39, 45, 48, 51, 60, 90, 102, 105, 111, 120, 150, 180, 201, 210, 249, 300, 318, 321, 348, 351, 390, 450, 480, 501, 510, 549, 600, 900, 1002, 1005, 1011, 1020, 1050, 1101, 1110, 1149, 1200, 1500, 1761, 1800, 2001, 2010, 2100, 2490

Offset

1,1

Comments

Subsequence of A008585.

Links

Robert Israel, Table of n, a(n) for n = 1..1000

Example

6 is in sequence because 6^2 = 36 and 3+6 = 9.

Maple

filter:= proc(n) convert(convert(n^2, base, 10), `+`) = 9 end proc:select(filter, [$1..10^5]); # Robert Israel, Jan 04 2024

Mathematica

Select[Range[10^5], Total[IntegerDigits[#^2]] == 9 &]

Prog

(Magma) [n: n in [1..2*10^4] | &+Intseq(n^2) eq 9 ];
(PARI) for(n=1, 1e8, if (sumdigits(n^2) == 9, print1(n", "))) \\ Altug Alkan, Sep 28 2015

Crossrefs

Cf. similar sequences listed in A262711.

Cf. A004159, A008585, A061910.

Sequence in context: A022844 A376955 A260702 * A195934 A195933 A110117

Adjacent sequences: A262709 A262710 A262711 * A262713 A262714 A262715

Keyword

nonn,base

Author

Vincenzo Librandi, Sep 28 2015

Status

approved