OFFSET
0,3
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..10000
FORMULA
G.f. A(x) satisfies: A(x) = x * (1 + 2*x + 3*x^2) * (1 + A(x^4)).
MATHEMATICA
Table[Times @@ IntegerDigits[n, 4], {n, 0, 100}]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Ilya Gutkovskiy, Aug 24 2019
STATUS
approved