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 A125112 Numbers which are not the sum of 3 nonzero squares, but which can be expressed as the product of two numbers that are the sum of 3 nonzero squares. 0
 63, 87, 135, 156, 159, 183, 207, 231, 252, 279, 303, 319, 327, 348, 351, 375, 399, 423, 444, 447, 471, 476, 495, 519, 540, 543, 551, 567, 572, 583, 591, 615, 624, 636, 639, 663, 671, 687, 700, 711, 732, 735, 759, 783, 807, 828, 831, 847, 855, 879, 903, 924 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A004214 with products of pairs of terms of A000408. LINKS EXAMPLE a(2) = 87 = 3 * 29 = (1^2+1^2+1^2) * (4^2+3^2+2^2) 87 does not have a partition as a sum x^2+y^2+z^2 with x,y,z>0 63=3*21; 87=3*29; 135=3*45; 156=6*26; 572=22*26; MAPLE isA000408 := proc(n) local a, b, c2 ; a:=1; while a^2

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