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 A076663 a(n) = sum of sigma(e) where e ranges over all non-divisors of n that are between 1 and n. 0
 0, 0, 3, 4, 14, 13, 32, 30, 51, 59, 86, 72, 126, 129, 154, 163, 219, 205, 276, 262, 326, 355, 406, 361, 484, 504, 546, 561, 659, 622, 761, 737, 840, 883, 944, 900, 1097, 1112, 1177, 1160, 1341, 1300, 1479, 1465, 1560, 1658, 1757, 1645, 1921, 1928, 2057, 2085 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Table of n, a(n) for n=1..52. MATHEMATICA f[n_] := Module[{s, i}, s = 0; For[i = 1, i < n, i++, If[Mod[n, i] != 0, s = s + DivisorSigma[1, i]]]; s]; Table[f[i], {i, 1, 100}] CROSSREFS Sequence in context: A337297 A220846 A009286 * A277933 A278953 A280608 Adjacent sequences: A076660 A076661 A076662 * A076664 A076665 A076666 KEYWORD nonn AUTHOR Joseph L. Pe, Oct 24 2002 STATUS approved

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Last modified August 2 21:27 EDT 2024. Contains 374875 sequences. (Running on oeis4.)