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A333120 a(1) = 1, a(n+1) = Sum_{d|n} a(d)^2. 0
1, 1, 2, 5, 27, 730, 532906, 283988804837, 80649641272747674596596, 6504364637422885153991868441922618991334787221, 42306759336557340251452848811862268800945638555088445693345741249091605099189510505344903572 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..11.

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

Cf. A003238, A007018, A082588.

Sequence in context: A079716 A322151 A203195 * A058182 A057438 A002795

Adjacent sequences:  A333117 A333118 A333119 * A333121 A333122 A333123

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Mar 08 2020

STATUS

approved

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Last modified August 3 05:55 EDT 2020. Contains 336197 sequences. (Running on oeis4.)