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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

Harvey P. Dale, Table of n, a(n) for n = 2..449

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

Adjacent sequences:  A110370 A110371 A110372 * A110374 A110375 A110376

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 November 27 16:20 EST 2021. Contains 349394 sequences. (Running on oeis4.)