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 A009633 E.g.f. tan(cos(x)*x) (odd powers only). 5
 1, -1, -39, 55, 39697, -2289, -235548247, -1367615353, 4617417380769, 85802560805023, -226896487004217095, -9332987296855749801, 23509703520941274769841, 1792438008018628579394735 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA a(n)=sum(k=0..n, binomial(2*n+1,2*k+1)*(sum(i=0..k,(2*k+1-2*i)^(2*n-2*k)*binomial(2*k+1,i)))*(sum(j=1..2*k+1, j!*2^(1-j)*(-1)^(n+1+j)*stirling2(2*k+1,j)))). - Vladimir Kruchinin, Jun 18 2011 PROG (Maxima) a(n):=sum(binomial(2*n+1, 2*k+1)*(sum((2*k+1-2*i)^(2*n-2*k)*binomial(2*k+1, i), i, 0, k))*(sum(j!*2^(1-j)*(-1)^(n+1+j)*stirling2(2*k+1, j), j, 1, 2*k+1)), k, 0, n); /* Vladimir Kruchinin, Jun 18 2011 */ CROSSREFS Sequence in context: A268083 A063480 A305026 * A156333 A116281 A168530 Adjacent sequences:  A009630 A009631 A009632 * A009634 A009635 A009636 KEYWORD sign AUTHOR EXTENSIONS Extended with signs by Olivier Gérard, Mar 15 1997 STATUS approved

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Last modified August 17 11:51 EDT 2019. Contains 326057 sequences. (Running on oeis4.)