

A203422


Reciprocal of Vandermonde determinant of (1/2,1/3,...,1/(n+1)).


4



1, 6, 288, 144000, 933120000, 94097687040000, 172670008499896320000, 6607002383077924814192640000, 5946302144770132332773376000000000000, 140210694122490812598274255654748160000000000000
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OFFSET

1,2


COMMENTS

Each term divides its successor, as in A203423.


LINKS



FORMULA

a(n) = (n+1)^(n1) * Product_{i=2..n} (i)^(i1).  Kevin Ryde, Apr 17 2022


MATHEMATICA

f[j_] := 1/(j + 1); z = 16;
v[n_] := Product[Product[f[k]  f[j], {j, 1, k  1}], {k, 2, n}]
1/Table[v[n], {n, 1, z}] (* A203422 *)
Table[v[n]/(2 v[n + 1]), {n, 1, z  1}] (* A203423 *)


PROG

(PARI) a(n) = my(f=n+1); prod(i=n, 2, f*=i); \\ Kevin Ryde, Apr 17 2022


CROSSREFS



KEYWORD

sign,easy


AUTHOR



STATUS

approved



