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A262711
Numbers n such that sum of digits of n^2 is 7.
2
4, 5, 32, 40, 49, 50, 149, 320, 400, 490, 500, 1049, 1490, 3200, 4000, 4900, 5000, 10490, 14900, 32000, 40000, 49000, 50000, 104900, 149000, 320000, 400000, 490000, 500000, 1049000, 1490000, 3200000, 4000000, 4900000, 5000000, 10490000, 14900000
OFFSET
1,1
COMMENTS
Subsequence of A156638. [Bruno Berselli, Sep 28 2015]
EXAMPLE
4 is in sequence because 4^2 = 16 and 1+6 = 7.
MATHEMATICA
Select[Range[10^7], Total[IntegerDigits[#^2]] == 7 &]
PROG
(Magma) [n: n in [1..2*10^7] | &+Intseq(n^2) eq 7];
(PARI) for(n=1, 1e8, if (sumdigits(n^2) == 7, print1(n", "))) \\ Altug Alkan, Sep 28 2015
CROSSREFS
Cf. sum of digits of n^2 is k: A052216 (k=4), this sequence (k=7), A262712 (k=9), A262713 (k=10).
Sequence in context: A271200 A335526 A373190 * A215614 A013468 A376536
KEYWORD
nonn,base
AUTHOR
Vincenzo Librandi, Sep 28 2015
STATUS
approved