A092960 - OEIS

A092960

Least square of the form 'sum of n successive terms of a geometric progression + 1', or 0 if no such square exists.

1, 4, 36, 16, 900, 64, 15876, 256, 47524, 1024, 386884, 4096, 67076100, 16384, 21921124, 65536, 17179344900, 262144, 274875809796, 1048576, 148371336100, 4194304, 9206236135684, 16777216, 1167694198801, 67108864, 367640742081600, 268435456, 3836162239297600

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OFFSET

1,2

COMMENTS

Conjecture: No term is zero.

If n is even, a(n) = 2^n. - Ray G. Opao, Feb 25 2005

LINKS

Table of n, a(n) for n=1..29.

EXAMPLE

a(3) = 36 = (5 + 10 + 20) + 1. a(4) = 16 = (1 + 2 + 4 + 8) + 1.

CROSSREFS

Cf. A092959.