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A102761
Same as A000179, except that a(0) = 2.
11
2, -1, 0, 1, 2, 13, 80, 579, 4738, 43387, 439792, 4890741, 59216642, 775596313, 10927434464, 164806435783, 2649391469058, 45226435601207, 817056406224416, 15574618910994665, 312400218671253762, 6577618644576902053, 145051250421230224304, 3343382818203784146955, 80399425364623070680706, 2013619745874493923699123
OFFSET
0,1
COMMENTS
For any integer n>=0, 2 * Integral_{t=-2..2} T_n(t/2)*exp(-t)*dt = 4 * Integral_{z=-1..1} T_n(z)*exp(-2*z)*dz = a(n)*exp(2) - A300484(n)*exp(-2). - Max Alekseyev, Mar 08 2018
REFERENCES
J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 197.
FORMULA
a(n) = Sum_{i=0..n} A127672(n,i) * A000023(i). - Max Alekseyev, Mar 06 2018
a(n) = A300481(2,n) = A300480(-2,n). - Max Alekseyev, Mar 06 2018
a(n) = A335391(0,n) (Touchard). - William P. Orrick, Aug 29 2020
PROG
(PARI) { A102761(n) = subst( serlaplace( 2*polchebyshev(n, 1, (x-2)/2)), x, 1); } \\ Max Alekseyev, Mar 06 2018
CROSSREFS
Row m=2 in A300481.
A000179, A102761, and A335700 are all essentially the same sequence but with different conventions for the initial terms a(0) and a(1). - N. J. A. Sloane, Aug 06 2020
Sequence in context: A332032 A298878 A195982 * A231119 A129558 A353414
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Apr 04 2010, following a suggestion from Vladimir Shevelev
EXTENSIONS
Changed a(0)=2 (making the sequence more consistent with existing formulae) by Max Alekseyev, Mar 06 2018
STATUS
approved