OFFSET
1,4
COMMENTS
T(n,k) = (-k)^(k-1) * k^(n-k) * binomial(n,k) for k>0, while T(n,0)=0 by convention.
LINKS
Stanislav Sykora, Table of n, a(n) for rows 1..100
S. Sykora, An Abel's Identity and its Corollaries, Stan's Library, Volume V, 2014, DOI 10.3247/SL5Math14.004. See eq.(11), with b=1.
FORMULA
E.g.f. A(x,y) satisfies: A(x,y) * exp( A(x,y) ) = y*x*exp(x). - Paul D. Hanna, Sep 13 2017
EXAMPLE
First rows of the triangle, starting at row n=1. All rows sum up to 0, except the first one whose sum is 1:
0, 1;
0, 2, -2;
0, 3, -12, 9;
0, 4, -48, 108, -64;
0, 5, -160, 810, -1280, 625;
0, 6, -480, 4860, -15360, 18750, -7776;
0, 7, -1344, 25515, -143360, 328125, -326592, 117649;
0, 8, -3584, 122472, -1146880, 4375000, -7838208, 6588344, -2097152; ...
From Paul D. Hanna, Sep 13 2017: (Start)
E.g.f.: A(x,y) = y*x + (-2*y^2 + 2*y)*x^2/2! + (9*y^3 - 12*y^2 + 3*y)*x^3/3! + (-64*y^4 + 108*y^3 - 48*y^2 + 4*y)*x^4/4! + (625*y^5 - 1280*y^4 + 810*y^3 - 160*y^2 + 5*y)*x^5/5! + (-7776*y^6 + 18750*y^5 - 15360*y^4 + 4860*y^3 - 480*y^2 + 6*y)*x^6/6! + (117649*y^7 - 326592*y^6 + 328125*y^5 - 143360*y^4 + 25515*y^3 - 1344*y^2 + 7*y)*x^7/7! +...
such that A(x,y) * exp( A(x,y) ) = y*x*exp(x). (End)
PROG
(PARI) seq(nmax, b)={my(v, n, k, irow);
v = vector((nmax+1)*(nmax+2)/2-1);
for(n=1, nmax, irow=n*(n+1)/2; v[irow]=0;
for(k=1, n, v[irow+k]=(-1)^(k-1)*(k*b)^(n-1)*binomial(n, k); ); );
return(v); }
a=seq(100, 1);
CROSSREFS
KEYWORD
sign,tabl
AUTHOR
Stanislav Sykora, Jun 22 2014
STATUS
approved