OFFSET
0,1
COMMENTS
a(n) is the smallest nonnegative k such that A119395(k) = n.
a(18) = 48412.
a(20) = 18384457.
a(21) = 6117748.
a(23) = 1623076.
a(24) = 214396.
a(27) = 629356.
a(30) = 2372188.
a(32) = 79530724.
a(36) = 1500772.
a(41) = 11957764.
a(42) = 116237212.
PROG
(PARI) b(n, k) = sum(i=0, sqrtint(n), sum(j=0, sqrtint(n\k), i^2+k*j^2==n));
a(n, k=3) = my(cnt=0); while(b(cnt, k)!=n, cnt++); cnt;
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Seiichi Manyama, Jul 02 2024
STATUS
approved