login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A000965 Numerators of expansion of sinh x / sin x.
(Formerly M1307 N0501)
1
1, 2, 4, 104, 272, 3104, 79808, 631936, 1708288, 7045156352, 1413417032704, 6587672324096, 37378439704576, 66465881481076736, 80812831866241024, 17004045797823707643904, 55131841948562370265088, 189924798793194975920128 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

REFERENCES

J. M. Gandhi, The coefficients of cosh x / cos x and a note on Carlitz's coefficients of sinh x / sin x, Math. Mag., 31 (1958), 185-191.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

FORMULA

Numerator of (2n)!/(2n+1) times coefficient of x^(2n) in sinh x / sin x.

EXAMPLE

1+1/3*x^2+1/18*x^4+13/1890*x^6+17/22680*x^8+...

CROSSREFS

Cf. A006656.

Sequence in context: A166094 A018440 A104050 * A018449 A156506 A018455

Adjacent sequences:  A000962 A000963 A000964 * A000966 A000967 A000968

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 13:28 EST 2012. Contains 206031 sequences.