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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A032036 Shifts left 3 places under "AIJ" (ordered, indistinct, labeled) transform. 1
1, 1, 1, 1, 3, 13, 75, 543, 4719, 47871, 555177, 7245015, 105069249, 1676322369, 29178875913, 550266979833, 11176051287627, 243213176948013, 5645877335588331, 139257558038636847, 3636985088689068231, 100266394939348499127, 2909740575643004791953, 88664517647380019280375 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200

FORMULA

a(n) = sum(k=0..n-4, binomial(n-3,k)*a(k+3)*a(n-k-3)), a(1)=a(2)=a(3)=1. - Vladimir Kruchinin, May 10 2011

E.g.f. A(x) satisfies differential equation A'''(x)-A(x)*A'''(x)=1, A'(0)=1, A''(0)=1, A'''(0)=1. - Vladimir Kruchinin, Nov 19 2011

PROG

(Maxima)

a(n):=if n=0 then 0 else if n<4 then 1 else sum(binomial(n-3, k)*a(k+3)*a(n-k-3), k, 0, n-4); /* Vladimir Kruchinin, May 10 2011 */

(PARI) seq(n)={my(p=x+x^2+O(x*x^(n%3))); for(i=1, n\3, p=intformal(1 + intformal(1 + intformal(1/(1-p))))); Vec(serlaplace(p))} \\ Andrew Howroyd, Sep 19 2018

CROSSREFS

Sequence in context: A276930 A034172 A000670 * A305535 A300793 A222427

Adjacent sequences:  A032033 A032034 A032035 * A032037 A032038 A032039

KEYWORD

nonn,eigen

AUTHOR

Christian G. Bower

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 22 06:02 EDT 2018. Contains 316432 sequences. (Running on oeis4.)