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A211234
Triangle read by rows: T(n,k) is the k-th generalized Eulerian number of order n and degree 4, n >= 1.
4
1, 2, 3, 4, 1, 4, 10, 20, 10, 4, 1, 1, 7, 27, 77, 57, 0, -57, -77, -27, -7, -1, 1, 12, 69, 272, 221, -272, -1084, -1688, -1084, -272, 221, 272, 69, 12, 1, 1, 21, 176, 936, 625, -3288, -11868, -21023, -16223, 0, 16223, 21023, 11868, 3288, -625, -936, -176, -21, -1
OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..1276 (rows 1..25)
D. H. Lehmer, Generalized Eulerian numbers, J. Combin. Theory Ser.A 32 (1982), no. 2, 195-215. MR0654621 (83k:10026).
FORMULA
A047683(n) = Sum_{k>=1} T(2*n, k). - Andrew Howroyd, May 18 2020
EXAMPLE
Triangle begins:
1, 2, 3, 4;
1, 4, 10, 20, 10, 4, 1;
1, 7, 27, 77, 57, 0, -57, -77, -27, -7, -1;
...
PROG
(PARI)
T(n, r=4)={my(R=vector(n)); R[1]=[1..r]; for(n=2, n, my(u=R[n-1]); R[n]=vector(r*n-1, k, sum(j=0, r, (k - j*n)*if(k>j && k-j<=#u, u[k-j], 0)))); R}
{ my(A=T(5)); for(n=1, #A, print(A[n])) } \\ Andrew Howroyd, May 18 2020
CROSSREFS
Row sums of even rows are A047683; row sums of odd rows are zero for n > 1.
Sequence in context: A248723 A117742 A117716 * A359122 A240185 A292032
KEYWORD
sign,tabf
AUTHOR
N. J. A. Sloane, Apr 05 2012
EXTENSIONS
More terms from Franck Maminirina Ramaharo, Nov 30 2018
a(20) corrected by Andrew Howroyd, May 18 2020
STATUS
approved