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A121563 Numerator of Sum[i=1..n] i!/(i^i). 2
1, 3, 31, 523, 333787, 3029083, 357534985867, 1466339436008107, 86629054728081110243, 54153614078975016066611, 1404709830784309760237846406097211, 1404749977001540310126014452972211 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Denominators are A121564. Limit as n approaches infinity of A121563(n)/A121564(n) = 1.879853862175258533486306145... whose decimal expansion is A094082.

LINKS

Table of n, a(n) for n=1..12.

FORMULA

Numerator of Sum[i=1..n] i!/(i^i) A000142(i)/A000312(i).

EXAMPLE

a(1) = 1/1 = 1.

a(2) = 3/2 = 1.5

a(3) = 31/18 = 1.72222222222.

a(4) = 523/288 = 1.81597222222.

a(5) = 333787/180000 = 1.85437222222.

CROSSREFS

Cf. A000142, A000312, A055775, A094082.

Sequence in context: A143637 A327227 A245109 * A261471 A273378 A266487

Adjacent sequences:  A121560 A121561 A121562 * A121564 A121565 A121566

KEYWORD

easy,frac,nonn

AUTHOR

Jonathan Vos Post, Aug 07 2006

STATUS

approved

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Last modified March 3 09:46 EST 2021. Contains 341760 sequences. (Running on oeis4.)