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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A001976 Number of partitions of floor(5n/2)-1 into n nonnegative integers each no more than 5.
(Formerly M2545 N1006)
0
1, 3, 6, 11, 19, 32, 48, 71, 101, 141, 188, 249, 322, 414, 518, 645, 791, 966, 1160, 1389, 1645, 1943, 2268, 2642, 3053, 3521, 4026, 4596, 5214, 5907, 6648, 7473, 8359, 9339, 10380, 11526, 12747, 14085, 15498, 17039, 18671, 20444, 22308, 24326, 26452 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

In Cayley's terminology, this is the number of literal terms of degree n and of weight floor(5n/2)-1 involving the letters a, b, c, d, e, f, having weights 0, 1, 2, 3, 4, 5 respectively. - Herman Jamke (hermanjamke(AT)fastmail.fm), Feb 17 2008

REFERENCES

A. Cayley, Numerical tables supplementary to second memoir on quantics, Collected Mathematical Papers. Vols. 1-13, Cambridge Univ. Press, London, 1889-1897, Vol. 2, p. 276-281.

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).

LINKS

A. Cayley, Numerical tables supplementary to second memoir on quantics, Collected Mathematical Papers. Vols. 1-13, Cambridge Univ. Press, London, 1889-1897, Vol. 2, p. 276-281.

FORMULA

Coefficient of x^w*z^n in the expansion of 1/((1-z)(1-xz)(1-x^2z)(1-x^3z)(1-x^4z)(1-x^5z)), where w=floor(5n/2)-1. - Herman Jamke (hermanjamke(AT)fastmail.fm), Feb 17 2008

PROG

(PARI) f=1/((1-z)*(1-x*z)*(1-x^2*z)*(1-x^3*z)*(1-x^4*z)*(1-x^5*z)); n=350; p=subst(subst(f, x, x+x*O(x^n)), z, z+z*O(z^n)); for(d=1, 60, w=floor(5*d/2)-1; print1(polcoeff(polcoeff(p, w), d)", ")) - Herman Jamke (hermanjamke(AT)fastmail.fm), Feb 17 2008

CROSSREFS

Cf. A001975.

Sequence in context: A180415 A050228 A114089 * A144115 A183088 A116557

Adjacent sequences:  A001973 A001974 A001975 * A001977 A001978 A001979

KEYWORD

nonn

AUTHOR

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

EXTENSIONS

Better definition and more terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Feb 17 2008

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 16 07:10 EST 2012. Contains 205874 sequences.