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A110373 a(n) = Sum_{prime p <= n} n!/p. 7
1, 5, 20, 124, 744, 5928, 47424, 426816, 4268160, 50578560, 606942720, 8369256960, 117169597440, 1757543961600, 28120703385600, 498974747443200, 8981545453977600, 177051737331302400, 3541034746626048000 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,2
LINKS
EXAMPLE
a(7) = 7!(1/2 + 1/3 + 1/5 + 1/7) = 5928.
MAPLE
a:=proc(n) local s, i: s:=0: for i from 2 to n do if isprime(i)=true then s:=s+1/i else s:=s: fi: od: n!*s: end: seq(a(n), n=2..23); # Emeric Deutsch, Jul 24 2005
MATHEMATICA
Table[n! Total[1/Prime[Range[PrimePi[n]]]], {n, 20}] (* Harvey P. Dale, Mar 06 2017 *)
CROSSREFS
Cf. A110374.
Sequence in context: A208941 A209069 A301952 * A081067 A318250 A337292
KEYWORD
easy,nonn
AUTHOR
Amarnath Murthy, Jul 24 2005
EXTENSIONS
More terms from Emeric Deutsch, Jul 24 2005
STATUS
approved

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Last modified April 18 20:26 EDT 2024. Contains 371781 sequences. (Running on oeis4.)