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Squares which are the sum of at least three successive terms of a geometric progression.
1

%I #9 Sep 19 2024 16:34:33

%S 49,121,169,196,225,400,441,484,676,784,900,961,1089,1225,1521,1600,

%T 1764,1849,1936,2025,2401,2704,3025,3136,3249,3600,3844,3969,4225,

%U 4356,4900,5329,5625,5929,6084,6400,7056,7225,7396,7744,8100,8281,8649,9604

%N Squares which are the sum of at least three successive terms of a geometric progression.

%C The partial sums of three or more successive terms of the sequence (2^n), 1,2,4,8,16,32,... is given by 7,14,15,28,30,31,...hence the square of the terms of this sequence are members. The same can be extended for any sequence of the form k^n.

%e 49 is a member as 49=7^2 = 7 + 14 + 28.

%e 400 is a member as 400 = 20^2 = 1 + 7 + 7^2 + 7^3.

%Y Intersection of A000290 and A376298.

%K nonn

%O 1,1

%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 14 2003

%E More terms from _David Wasserman_, Jan 03 2005

%E Offset changed by _Andrew Howroyd_, Sep 19 2024