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A294040 a(n) = e*(Gamma(2*n,1) - Gamma(n,1)). 2
0, 1, 14, 321, 13684, 986345, 108504786, 16926795529, 3554627458376, 966858672295089, 330665665961417590, 138879579704199815921, 70273067330329989586044, 42163840398198057552632281, 29599015959535037299068127994, 24034400959142450300350904324985 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Robert Israel, Table of n, a(n) for n = 0..225

FORMULA

a(n) = Sum_{k=0..2n-1} (2n-1)!/k! - Sum_{k=0..n-1} (n-1)!/k! = A000522(2*n-1) - A000522(n-1). - Robert Israel, Nov 14 2017

MAPLE

a := n -> exp(1)*(GAMMA(2*n, 1) - GAMMA(n, 1)):

seq(simplify(a(n)), n=0..15);

# Alternative:

A000522:= gfun:-rectoproc({(-x-2)*d(1+x)+(x+4)*d(x+2)-d(x+3), d(0) = 1, d(1) = 2, d(2) = 5}, d(x), remember):

0, seq(A000522(2*n-1)-A000522(n-1), n=1..30); # Robert Israel, Nov 14 2017

CROSSREFS

Cf. A000522, A294039.

Sequence in context: A341501 A255857 A239782 * A035018 A264177 A275500

Adjacent sequences:  A294037 A294038 A294039 * A294041 A294042 A294043

KEYWORD

nonn

AUTHOR

Peter Luschny, Nov 14 2017

STATUS

approved

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Last modified October 4 09:28 EDT 2022. Contains 357239 sequences. (Running on oeis4.)