OFFSET
1,3
FORMULA
a(n) ~ c^(2^n), where c = 1.10850959824748299278192262396861284785509520261602375885447280659977154... - Vaclav Kotesovec, Mar 08 2020
MATHEMATICA
a[1] = 1; a[n_] := a[n] = Sum[a[d]^2, {d, Divisors[n - 1]}]; Table[a[n], {n, 1, 11}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Mar 08 2020
STATUS
approved