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A079858 Power series coefficients of 1/(cos(2x)-sin(2x)). 1
1, 2, 12, 88, 912, 11552, 176832, 3150208, 64188672, 1470996992, 37459479552, 1049279715328, 32063706796032, 1061443378552832, 37841217707753472, 1445427909919080448, 58892032991566036992, 2549444593020567683072 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

E.g.f.: 1/(cos(2x)-sin(2x)).

PROG

(PARI) a(n)=if(n<0, 0, n!*polcoeff(1/(cos(2*x+x*O(x^n))-sin(2*x+x*O(x^n))), n))

CROSSREFS

Equals 2^n * A001586(n).

Sequence in context: A059435 A192621 A143923 * A174356 A121357 A098926

Adjacent sequences:  A079855 A079856 A079857 * A079859 A079860 A079861

KEYWORD

nonn,easy

AUTHOR

Michael Somos, Jan 20 2003

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Last modified February 15 19:15 EST 2012. Contains 205852 sequences.