A282570 - OEIS

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A282570

Number of ways to write n as an ordered sum of two multiplicatively perfect numbers (A007422).

0, 0, 1, 0, 0, 0, 0, 2, 0, 2, 0, 2, 1, 0, 2, 2, 5, 0, 2, 0, 3, 2, 4, 4, 2, 2, 0, 4, 5, 4, 3, 2, 4, 2, 4, 6, 8, 4, 0, 4, 6, 8, 5, 6, 5, 4, 2, 8, 10, 8, 2, 0, 7, 6, 7, 4, 8, 4, 2, 8, 10, 12, 2, 6, 4, 10, 9, 6, 9, 4, 7, 6, 14, 12, 2, 6, 5, 10, 7, 10, 8, 4, 4, 10, 14, 8, 6, 6, 10, 8, 10, 12, 15, 8, 6, 14

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OFFSET

0,8

COMMENTS

Conjecture: a(n) > 0 for all n > 51.

LINKS

Table of n, a(n) for n=0..95.

Ilya Gutkovskiy, Extended graphical example

Eric Weisstein's World of Mathematics, Multiplicative Perfect Number

FORMULA

G.f.: (Sum_{k>=1} x^A007422(k))^2.

EXAMPLE