|
|
A129465
|
|
Third column (m=2) sequence of triangle A129462 (v=2 member of a certain family).
|
|
4
|
|
|
1, 1, -4, -204, -7776, -358560, -20839680, -1516112640, -135920332800, -14772931891200, -1917601910784000, -293337284308992000, -52263416690343936000, -10734227287227924480000, -2518467729187335045120000, -669569466986357627289600000
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
COMMENTS
|
See A129462 for the M. Bruschi et al. reference.
|
|
LINKS
|
|
|
FORMULA
|
a(n) = (-1)*n!*(n+2)!*(HarmonicNumber(n+2) - 2), for n >= 1, otherwise a(0) = 1. - G. C. Greubel, Feb 08 2024
|
|
MATHEMATICA
|
A129465[n_]:= If[n==0, 1, -n!*(n+2)!*(HarmonicNumber[n+2] -2)];
|
|
PROG
|
(Magma)
A129465:= func< n | n eq 0 select 1 else -Factorial(n)*Factorial(n+2)*(HarmonicNumber(n+2) -2) >;
(SageMath)
def A129465(n): return 1 if (n==0) else -factorial(n)*factorial(n+2)*( harmonic_number(n+2) -2)
|
|
CROSSREFS
|
|
|
KEYWORD
|
sign,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|