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A325451
Numbers k such that sum of digits (k) and sum of digits (k^2) is 10.
1
19, 46, 55, 145, 190, 361, 451, 460, 550, 1450, 1900, 3610, 4510, 4600, 5500, 14500, 19000, 20251, 36100, 45100, 46000, 55000, 145000, 190000, 202510, 361000, 451000, 460000, 550000, 1450000, 1900000, 2025100, 3610000, 4510000, 4600000, 5500000, 14500000
OFFSET
1,1
COMMENTS
Subsequence of A058369 (k and k^2 have same digit sum).
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.
EXAMPLE
a(4) = 145 because 1+4+5 = 10, 145^2 = 21025, and 2+1+0+2+5 = 10.
MATHEMATICA
Select[Range[2 10^7], Total[IntegerDigits[#]]==10 && Total[IntegerDigits[#^2]]==10 &]
PROG
(Magma) [n: n in [1..2*10^7] | &+Intseq(n^2) eq 10 and &+Intseq(n) eq 10];
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Vincenzo Librandi, May 10 2019
STATUS
approved