Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A006233
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A006233 Denominators of Cauchy numbers of first type.
(Formerly M1558)
+0
13
1, 2, 6, 4, 30, 4, 84, 24, 90, 20, 132, 8, 5460, 840, 360, 48, 1530, 4, 1596, 168, 1980, 1320, 8280, 80, 81900, 6552, 1512, 112, 3480, 80, 114576, 7392, 117810, 7140, 1260, 8, 3838380, 5928, 936, 48, 81180 (list; graph; listen)
OFFSET

0,2

COMMENT

The signed rationals A006232(n)/a(n) provide the a-sequence for the Stirling2 Sheffer matrix A048993. See the W. Lang link concerning Sheffer a- and z-sequences.

Cauchy numbers of the first type are also called Bernoulli numbers of the second kind.

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 294.

H. Jeffreys and B. S. Jeffreys, Methods of Mathematical Physics, Cambridge, 1946, p. 259.

A. Adelberg, 2-adic congruences of Norland numbers and of Bernoulli numbers of the second kind, J. Number Theory, 73 (1998), 47-58.

Ming Wu and Hao Pan, Sums of products of Bernoulli numbers of the second kind, Fib. Quart., 45 (2007), 146-150.

LINKS

T. D. Noe, Table of n, a(n) for n=0..1000

W. Lang, Sheffer a- and z-sequences.

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

FORMULA

Denominator of integral of x(x-1)...(x-n+1) from 0 to 1.

E.g.f.: x/log(1+x).

EXAMPLE

1, 1/2, -1/6, 1/4, -19/30, 9/4, -863/84, 1375/24, -33953/90,...

CROSSREFS

Cf. A006232, A002206, A002207, A002208, A002209, A002657, A002790.

Sequence in context: A106831 A038212 A039656 this_sequence A057643 A073039 A064538

Adjacent sequences: A006230 A006231 A006232 this_sequence A006234 A006235 A006236

KEYWORD

nonn,frac,nice,easy

AUTHOR

njas

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified July 24 12:00 EDT 2008. Contains 142294 sequences.


AT&T Labs Research