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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A000527 Series-parallel numbers.
(Formerly M5304 N2306)
0
52, 472, 3224, 18888, 101340, 511120, 2465904, 11496144, 52165892, 231557064, 1009247192, 4331502840, 18346242492, 76822836544, 318485778848, 1308750158016, 5335993098340, 21603437175288, 86912657626392, 347660876627944, 1383457374046444, 5479086968052912, 21604984733546336, 84850331177724944, 332001521469767940, 1294589169323791912, 5031934808360234760, 19500424806065865400, 75360646947991208396, 290478417300879735680, 1116919455364101145920, 4284817000807140094464, 16402243457215852326116, 62659647762404302956856, 238910441445219175239480 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,1

REFERENCES

J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 142.

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

Table of n, a(n) for n=4..38.

FORMULA

G.f.: 4(13+14S+3S^2)(1+S)/(1-S)^7, where S = g.f. for A000084. - Sean A. Irvine, Nov 14 2010

MATHEMATICA

n = 35; s = 1/(1 - x) + O[x]^(n + 1); Do[s = s/(1 - x^k)^Coefficient[s, x^k] + O[x]^(n + 1), {k, 2, n}] ; S = s - 1; CoefficientList[4 (13 + 14 S + 3 S^2) (1 + S)/(1 - S)^7 + O[x]^n, x] (* Jean-Fran├žois Alcover, Feb 09 2016 *)

CROSSREFS

Sequence in context: A257940 A005946 A200549 * A294055 A285753 A100413

Adjacent sequences:  A000524 A000525 A000526 * A000528 A000529 A000530

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Sean A. Irvine, Nov 14 2010

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 14 05:36 EST 2019. Contains 329978 sequences. (Running on oeis4.)