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 A078155 A078152(n!). 4
 0, 0, 0, 0, 4, 22, 80, 304, 1043, 3538, 12094, 42979, 156237, 587926, 2283038, 9142910, 37708601, 160014979, 697523776, 3119511496, 14295524835, 67052144163, 321571055089, 1575370699764, 7876854373196, 40164235356266, 208699490940770 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 LINKS Michael De Vlieger, Table of n, a(n) for n = 1..807 FORMULA a(n) = A078152(n!) = A055086(n!) - A000005(n!). MATHEMATICA Table[ Length[ Union[ Table[ Floor[w!/j], {j, 1, w!}]]] - DivisorSigma[0, w! ], {w, 1, 11}] (* Second program: *) Array[Floor@ Sqrt[4 # + 1] - 1 - DivisorSigma[0, #] &[#!] &, 27] (* Michael De Vlieger, Dec 13 2018 *) CROSSREFS Cf. A078152, A078153, A078154, A078156, A078157, A078158. Sequence in context: A062966 A201127 A259709 * A237530 A096167 A060453 Adjacent sequences:  A078152 A078153 A078154 * A078156 A078157 A078158 KEYWORD nonn AUTHOR Labos Elemer, Nov 27 2002 EXTENSIONS Extended by Robert G. Wilson v, Dec 02 2002 a(11) corrected and terms a(12) onward added by Max Alekseyev, Feb 12 2012 STATUS approved

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Last modified September 21 07:06 EDT 2020. Contains 337267 sequences. (Running on oeis4.)