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A009670
E.g.f. tan(sin(x)*cos(x)) (odd powers only).
1
1, -2, -48, 880, 59136, -4558336, -358510592, 87349164032, 5261729398784, -4294386293800960, -9972473469599744, 442881767885962739712, -50940651947982996897792, -83250857495799899292172288
OFFSET
0,2
FORMULA
a(n)=2*sum(m=0..n, 4^(n-m)*((sum(j=1..2*m+1, j!*2^(-j)*(-1)^(j+1)*stirling2(2*m+1, j)))*sum(i=0..(2*m+1)/2, (2*i-(2*m+1))^(2*n+1)*binomial(2*m+1, i)*(-1)^(n+1-i)))/(2*m+1)!). - Vladimir Kruchinin, Jun 29 2011
PROG
(Maxima)
a(n):=2*sum(4^(n-m)*((sum(j!*2^(-j)*(-1)^(j+1)*stirling2(2*m+1, j), j, 1, 2*m+1))*sum((2*i-(2*m+1))^(2*n+1)*binomial(2*m+1, i)*(-1)^(n+1-i), i, 0, (2*m+1)/2))/(2*m+1)!, m, 0, n); /* Vladimir Kruchinin, Jun 28 2011 */
CROSSREFS
Cf. A101921.
Sequence in context: A290690 A013523 A260846 * A024236 A119703 A012803
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved