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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A115140 O.g.f. inverse of Catalan A000108 o.g.f. 9
1, -1, -1, -2, -5, -14, -42, -132, -429, -1430, -4862, -16796, -58786, -208012, -742900, -2674440, -9694845, -35357670, -129644790, -477638700, -1767263190, -6564120420, -24466267020, -91482563640, -343059613650, -1289904147324, -4861946401452, -18367353072152 (list; graph; refs; listen; history; internal format)
OFFSET

0,4

FORMULA

See A034807 and A115149 for comments.

For convolutions of this sequence see A115141-A115149.

O.g.f. 1/c(x) = 1-x*c(x) with the o.g.f. c(x):=(1-sqrt(1-4*x))/(2*x) of A000108 (Catalan numbers).

a(0)=1, a(n)=-C(n-1), n>=1, with C(n):=A000108(n) (Catalan).

CROSSREFS

Sequence in context: A033191 A168491 * A120588 A000108 A057413 A126567

Adjacent sequences:  A115137 A115138 A115139 * A115141 A115142 A115143

KEYWORD

sign,easy

AUTHOR

Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Jan 13 2006

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 15 21:16 EST 2012. Contains 205856 sequences.