The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A013515 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing all changes.

A013515

sech(sec(x)-sech(x))=1-12/4!*x^4+1568/8!*x^8+6840768/12!*x^12...
(history; published version)

#9 by Jon E. Schoenfield at Sun Aug 02 21:09:16 EDT 2015

STATUS

editing

approved

#8 by Jon E. Schoenfield at Sun Aug 02 21:09:14 EDT 2015

MAPLE

end proc: # _R. J. Mathar, _, Dec 16 2011

STATUS

approved

editing

#7 by Charles R Greathouse IV at Fri Feb 24 12:51:32 EST 2012

AUTHOR

Patrick Demichel (dmlpatrick.demichel(AT)hpfrcu03.france.hp.com)

Discussion

Fri Feb 24

12:51

OEIS Server: https://oeis.org/edit/global/108

#6 by R. J. Mathar at Fri Dec 16 15:50:04 EST 2011

STATUS

editing

approved

#5 by R. J. Mathar at Fri Dec 16 15:49:54 EST 2011

MAPLE

A013515 := proc(n)

sech(sec(x)-sech(x)) ;

coeftayl( %, x=0, 4*n) ;

%*(4*n)! ;

end proc: # R. J. Mathar, Dec 16 2011

STATUS

approved

editing

#4 by N. J. A. Sloane at Fri May 16 03:00:00 EDT 2003

KEYWORD

sign,done,new

sign

AUTHOR

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

#3 by N. J. A. Sloane at Sat Dec 11 03:00:00 EST 1999

DATA

1, -12, 1568, 6840768, -41485549312, -616649036623872, 51689032519042469888, 309411873154808535072768,

KEYWORD

sign,done,new

#2 by N. J. A. Sloane at Sun Jun 14 03:00:00 EDT 1998

REFERENCES

KEYWORD

sign,done,new

#1 by N. J. A. Sloane at Wed Dec 11 03:00:00 EST 1996

NAME

sech(sec(x)-sech(x))=1-12/4!*x^4+1568/8!*x^8+6840768/12!*x^12...

DATA

1, -12, 1568, 6840768, -41485549312, -616649036623872, 51689032519042469888, 309411873154808535072768,

OFFSET

0,2

REFERENCES

KEYWORD

sign,done

AUTHOR

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

STATUS

approved