OFFSET
1,3
COMMENTS
If n is in the sequence, then so is 10*n. - Robert Israel, Dec 27 2018
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
67^2=4489, 4+4+8=16=4^2, 9=3^2; 115^2=13225, 2+2=4=2^2, 1+3+5=9=3^2.
MAPLE
filter:= proc(n) local L, E, O;
L:= convert(n^2, base, 10);
E, O:= selectremove(type, L, even);
issqr(convert(E, `+`)) and issqr(convert(O, `+`))
end proc:
select(filter, [$0..2000]); # Robert Israel, Dec 27 2018
PROG
(PARI) isok(n) = {d = digits(n^2); sed = sum(i=1, #d, !(d[i]%2)*d[i]); sod = sum(i=1, #d, (d[i]%2)*d[i]); issquare(sed) && issquare(sod); } \\ Michel Marcus, Oct 15 2013
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Feb 10 2010
STATUS
approved