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a(n) = A087475(n)*A053755(n).
Table of n, a(n) for n=0..31.
a(n) = (2*(n^2 - 1))^2 + (5*n)^2.
G.f.:(-4-25*x^4-11*x^3-51*x^2-5*x)/(x-1)^5 [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 26 2009]
(MAGMA)[4*n^4+17*n^2+4: n in [0..50]]; [From Vincenzo Librandi, Dec 27 2010]
Sequence in context: A263440 A240631 A123660 * A220381 A015533 A207410
Adjacent sequences: A156698 A156699 A156700 * A156702 A156703 A156704
Reinhard Zumkeller, Feb 13 2009