A215926 - OEIS

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A215926

Smallest deficient number k such that the product k*n is non-deficient (perfect or abundant).

3, 2, 3, 4, 1, 4, 3, 2, 2, 8, 1, 8, 2, 2, 3, 16, 1, 16, 1, 2, 3, 16, 1, 4, 3, 2, 1, 16, 1, 16, 3, 2, 3, 2, 1, 32, 3, 2, 1, 32, 1, 32, 2, 2, 3, 32, 1, 4, 2, 2, 2, 32, 1, 4, 1, 2, 3, 32, 1, 32, 3, 2, 3, 4, 1, 64, 3, 2, 1, 64, 1, 64, 3, 2, 3, 4, 1, 64, 1, 2, 3

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OFFSET

2,1

COMMENTS

If n is perfect or abundant then a(n) = 1.

Conjecture: a(n) is 1, 3, or a power of 2.

Conjecture: The first occurrence of 2^m happens at A014210(m).

LINKS

Michel Marcus, Table of n, a(n) for n = 2..1000

EXAMPLE

a(3) = 2 since 2*3 is perfect.

MATHEMATICA