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 A054025 Sum of divisors of n read modulo (number of divisors of n). 11
 0, 1, 0, 1, 0, 0, 0, 3, 1, 2, 0, 4, 0, 0, 0, 1, 0, 3, 0, 0, 0, 0, 0, 4, 1, 2, 0, 2, 0, 0, 0, 3, 0, 2, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 4, 0, 3, 0, 2, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 2, 1, 0, 0, 0, 0, 0, 0, 0, 3, 0, 2, 4, 2, 0, 0, 0, 6, 1, 2, 0, 8, 0, 0, 0, 4, 0, 6, 0, 0, 0, 0, 0, 0, 0, 3, 0, 1, 0, 0, 0, 2, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,8 COMMENTS a(A003601(n)) = 0; a(A049642(n)) > 0. [Reinhard Zumkeller, Jan 06 2012] LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A000203(n) mod A000005(n), sigma(n) mod tau(n). MAPLE with(numtheory): seq(sigma(i) mod tau(i), i=1..120); MATHEMATICA Table[Mod[DivisorSigma[1, n], DivisorSigma[0, n]], {n, 110}] (* Harvey P. Dale, Nov 16 2011 *) PROG (Haskell) import Data.List (genericIndex) a054025 n = genericIndex a054025_list (n-1) a054025_list = zipWith mod a000203_list a000005_list -- Reinhard Zumkeller, Jul 28 2014, Jan 06 2012 (PARI) vector(90, n, sigma(n) % numdiv(n)) \\ Michel Marcus, Aug 15 2015 CROSSREFS Cf. A000005, A000203. Cf. A003601, A049642, A245656. Sequence in context: A190561 A074735 A074090 * A265910 A222212 A318526 Adjacent sequences:  A054022 A054023 A054024 * A054026 A054027 A054028 KEYWORD nonn AUTHOR Asher Auel (asher.auel(AT)reed.edu), Jan 19 2000 STATUS approved

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Last modified December 4 13:03 EST 2021. Contains 349526 sequences. (Running on oeis4.)