login
A025314
Numbers that are the sum of 2 distinct nonzero squares in 4 or more ways.
5
1105, 1625, 1885, 2125, 2210, 2405, 2465, 2665, 3145, 3250, 3445, 3485, 3625, 3770, 3965, 4225, 4250, 4420, 4505, 4625, 4745, 4810, 4930, 5125, 5185, 5330, 5365, 5525, 5785, 5945, 6205, 6290, 6305, 6409, 6500, 6565, 6625, 6890, 6970, 7085, 7225, 7250
OFFSET
1,1
COMMENTS
Subsequence of A025295. But sequences A025295 and A025314 are different, A025295(346) = 31250 = 175^2 + 25^2 = 161^2 + 73^2 = 155^2 + 85^2 = 125^2 + 125^2 (not distinct squares) is not in A025314. - Vaclav Kotesovec, Feb 27 2016
Numbers in A025295 but not in A025314 are exactly those numbers of the form 2*p_1^(2*a_1)*p_2^(2*a_2)*...*p_m^(2*a_m)*q^6 where p_i are primes of the form 4k+3 and q is a prime of the form 4k+1. Thus 2*5^6 = 31250 is the smallest term in A025295 that is not in A025314. - Chai Wah Wu, Feb 27 2016
MATHEMATICA
nn = 7250; t = Table[0, {nn}]; lim = Floor[Sqrt[nn - 1]]; Do[num = i^2 + j^2; If[num <= nn, t[[num]]++], {i, lim}, {j, i - 1}]; Flatten[Position[t, _?(# >= 4 &)]] (* T. D. Noe, Apr 07 2011 *)
CROSSREFS
Sequence in context: A321870 A257759 A025295 * A025287 A025305 A052155
KEYWORD
nonn
STATUS
approved