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 A024385 a(n) = [ (2nd elementary symmetric function of S(n))/(first elementary symmetric function of S(n)) ], where S(n) = {first n+1 positive integers congruent to 1 mod 4}. 0
 0, 3, 9, 16, 25, 36, 49, 64, 82, 101, 122, 145, 170, 197, 227, 258, 291, 326, 363, 402, 444, 487, 532, 579, 628, 679, 733, 788, 845, 904, 965, 1028, 1094, 1161, 1230, 1301, 1374, 1449, 1527, 1606, 1687, 1770, 1855, 1942 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA Conjecture: a(n) = 2*a(n-1) - a(n-2) + a(n-6) - 2*a(n-7) + a(n-8). G.f. x^2*(-3-3*x-x^2-2*x^3-2*x^4-2*x^5+x^6) / ( (1+x)*(1+x+x^2)*(x^2-x+1)*(x-1)^3 ). - R. J. Mathar, Oct 08 2011 a(n) = floor(A024378(n) / A000384(n+1)). - Sean A. Irvine, Jul 06 2019 CROSSREFS Sequence in context: A253547 A290371 A109340 * A212566 A061942 A174440 Adjacent sequences:  A024382 A024383 A024384 * A024386 A024387 A024388 KEYWORD nonn AUTHOR STATUS approved

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Last modified May 29 07:50 EDT 2020. Contains 334697 sequences. (Running on oeis4.)