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!)
A300872 a(n) = A300871(n) / (n*(n+1)/2). 2
1, 1, 8, 151, 4752, 214848, 12915744, 986580860, 92994888960, 10595684332288, 1436363905680384, 228679178713630208, 42284602089642237952, 8992606241049735405568, 2180532527491138011131904, 598191016068264518151780096, 184370870332464252513762869248, 63445183762362816656030378164224, 24238363163428954774170892697075712 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

It is conjectured that this sequence consists entirely of integers.

O.g.f. G(x) of A300871 satisfies: [x^n] exp( n*(n+1) * G(x) ) = n*(n+1) * [x^(n-1)] exp( n*(n+1) * G(x) ) for n>=1.

LINKS

Paul D. Hanna, Table of n, a(n) for n = 1..200

PROG

(PARI) {a(n) = my(A=[1]); for(i=1, n+1, A=concat(A, 0); V=Vec(Ser(A)^((#A-1)*(#A))); A[#A] = ((#A-1)*(#A)*V[#A-1] - V[#A])/(#A-1)/(#A) ); (1/(n*(n+1)/2))*polcoeff( log(Ser(A)), n)}

for(n=1, 20, print1(a(n), ", "))

CROSSREFS

Cf. A300871.

Sequence in context: A302063 A220559 A264642 * A217502 A229955 A249481

Adjacent sequences:  A300869 A300870 A300871 * A300873 A300874 A300875

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 14 2018

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 10 04:15 EST 2019. Contains 329885 sequences. (Running on oeis4.)