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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A274573 Column 2 of triangle A274570. 5
1, 3, 39, 1125, 56505, 4354923, 476265591, 70056231213, 13329387478113, 3184105899176739, 932720103991595919, 328710383679927689157, 137188135970104212440721, 66909975066823379752742835, 37706189062081696231083478647, 24312515006613477431766856702797, 17784145956730483348850500758855969, 14647274671009402833580157237962722147, 13492886769176913829412675003231182928079 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Triangle A274570 transforms diagonals in the array A274390 of coefficients of successive iterations of Euler's tree function (A000169).

LINKS

Paul D. Hanna, Table of n, a(n) for n = 0..38

PROG

(PARI) {T(n, k)=local(F=x,

LW=serreverse(x*exp(-x+x*O(x^(n+2)))), M, N, P, m=max(n, k));

M=matrix(m+3, m+3, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, LW)); polcoeff(F, c));

N=matrix(m+1, m+1, r, c, M[r, c]);

P=matrix(m+1, m+1, r, c, M[r+1, c]);

(n-k)!*(P~*N~^-1)[n+1, k+1]}

/* Print triangle A274570: */

for(n=0, 10, for(k=0, n, print1(T(n, k), ", ")); print(""))

/* Print this sequence, which is column 2 */

for(n=0, 20, print1(T(n+2, 2), ", "))

CROSSREFS

Cf. A274570, A274571, A274572, A274574.

Sequence in context: A258923 A326271 A276964 * A278750 A082159 A187536

Adjacent sequences:  A274570 A274571 A274572 * A274574 A274575 A274576

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Jun 28 2016

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 November 20 20:46 EST 2019. Contains 329347 sequences. (Running on oeis4.)