OFFSET
0,2
LINKS
Eric Weisstein's World of Mathematics, Primorial
FORMULA
G.f.: 2 - 1 / (Sum_{k>=0} prime(k)# * x^k).
MATHEMATICA
primorial[n_] := Product[Prime[k], {k, 1, n}]; a[n_] := a[n] = primorial[n] - Sum[primorial[k] a[n - k], {k, 1, n - 1}]; Table[a[n], {n, 0, 19}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Mar 17 2020
STATUS
approved