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 A110374 a(n) = Sum_{composite c <= n} n!/c. 7
 6, 30, 300, 2100, 21840, 236880, 2731680, 30048480, 400498560, 5206481280, 79117758720, 1273944672000, 21690789120000, 368743415040000, 6993068898816000, 132868309077504000, 2779011281958912000, 60792138929313792000, 1388517998616612864000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,1 LINKS Michael S. Branicky, Table of n, a(n) for n = 4..449 EXAMPLE a(8) = 8! * (1/4 + 1/6 + 1/8) = 21840. MAPLE a:=proc(n) local s, i :s:=0: for i from 4 to n do if isprime(i)=false then s:=s+1/i else s:=s: fi od: n!*s; end; seq(a(n), n=4..23); # Emeric Deutsch, Jul 24 2005 PROG (Python) from sympy import factorial, isprime, Rational def a(n): return factorial(n) * sum(Rational(1, c) for c in range(4, n+1) if not isprime(c)) print([a(n) for n in range(4, 23)]) # Michael S. Branicky, Jun 30 2021 CROSSREFS Cf. A110373. Sequence in context: A215288 A295611 A264641 * A232978 A332041 A201135 Adjacent sequences:  A110371 A110372 A110373 * A110375 A110376 A110377 KEYWORD easy,nonn AUTHOR Amarnath Murthy, Jul 24 2005 EXTENSIONS More terms from Emeric Deutsch, Jul 24 2005 a(21) and beyond from Michael S. Branicky, Jun 30 2021 STATUS approved

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Last modified December 5 10:11 EST 2021. Contains 349543 sequences. (Running on oeis4.)