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 A097022 a(n) = (sigma(2n^2)-3)/6. 3
 0, 2, 6, 10, 15, 32, 28, 42, 60, 77, 66, 136, 91, 142, 201, 170, 153, 302, 190, 325, 370, 332, 276, 552, 390, 457, 546, 598, 435, 1007, 496, 682, 864, 767, 883, 1270, 703, 952, 1189, 1317, 861, 1852, 946, 1396, 1875, 1382, 1128, 2216, 1400, 1952, 1995, 1921 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See A065764, A065765 and A097022. LINKS FORMULA a(n) = (A065765(n)-3)/6 = A000203(A001105(n) - 3)/6. PROG (PARI) a(n) = (sigma(2*n^2) - 3)/6; \\ Michel Marcus, Dec 20 2013 CROSSREFS Cf. A065764, A065765, A000203, A072682, A074627-A074630, A067051. Sequence in context: A050895 A184426 A293408 * A137236 A124198 A032426 Adjacent sequences:  A097019 A097020 A097021 * A097023 A097024 A097025 KEYWORD nonn AUTHOR Labos Elemer, Aug 24 2004 STATUS approved

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Last modified December 1 04:32 EST 2021. Contains 349426 sequences. (Running on oeis4.)