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 A181964 Sum of the sizes of normalizers of all the cyclic subgroups of Alternating Group of order n. 0
 1, 1, 6, 36, 240, 2160, 20160, 241920, 2903040, 39916800, 578793600, 9580032000, 161902540800, 3007651046400, 58845346560000, 1234444603392000, 26854400821248000, 624231436308480000, 15083992450695168000, 385614968295997440000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS For each cyclic subgroup of the Alternate group on n symbols, add the size of its normalizer (permutations leaving the subgroup invariant by conjugation). a(7) is remarquable because it is equal to the size of Alt(8). LINKS FORMULA a(n) = n!/2 * A046682(n). EXAMPLE Decomposing by number of cyclic subgroups * size of normalizer of subgroups a(5) = 1*60 + 4*15 + 6*10 + 0*60 + 10*6 = 240. a(6) = 1*360 + 8*45 + (18*20+18*20) + 8*45 + 10*36 = 2160. CROSSREFS Cf. A053529, A181950. Sequence in context: A153824 A001286 A180119 * A199422 A049431 A049428 Adjacent sequences:  A181961 A181962 A181963 * A181965 A181966 A181967 KEYWORD nonn,easy AUTHOR Olivier Gérard, Apr 04 2012 STATUS approved

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Last modified June 20 10:07 EDT 2021. Contains 345162 sequences. (Running on oeis4.)