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A013501 exp(sec(x)-exp(x))=1-x+1/2!*x^2-2/3!*x^3+9/4!*x^4-32/5!*x^5... 1
1, -1, 1, -2, 9, -32, 157, -828, 5481, -35496, 290649, -2290840, 22092829, -204459452, 2273871485, -24119527604, 303515669169, -3629239434576, 50931449481777, -677485393669744, 10484228007290613, -153504673218503140, 2595681901243781013, -41471161060916985516, 760471144497476539177, -13162910847523759863288 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

MAPLE

read transforms;

t1:=exp(sec(x)-exp(x)); #A013501

t2:=series(t1, x, 30);

t3:=SERIESTOLISTMULT(%);

CROSSREFS

Sequence in context: A150918 A150919 A150920 * A179230 A114853 A110376

Adjacent sequences:  A013498 A013499 A013500 * A013502 A013503 A013504

KEYWORD

sign

AUTHOR

Patrick Demichel (dml(AT)hpfrcu03.france.hp.com)

EXTENSIONS

More terms from N. J. A. Sloane, Dec 17 2011

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.