%I #16 Oct 05 2023 14:26:48
%S 1,1,5,19,163,1583,22889,359083,7333087,158961311,4832970889,
%T 143352404329,5504599450303,218267839327613,9689767354614569,
%U 442336304335214713,24058713912354871199,1386874962351747356011
%N a(n) = s(1)*s(2)*...*s(n)*(1/s(1) - 1/s(2) + ... + c/s(n)), where s(1) = 1, s(k) = p(k-1) for k >= 2 and c = (-1)^(n+1).
%F a(n+1) = a(n)*prime(n) + (-1)^n*primorial(prime(n-1)) for n >= 3. - _Alexandre Herrera_, Sep 03 2023
%o (PARI) a(n)=if(n<1,n>0,prod(i=1,n-1, prime(i))*sum(i=1,n-1,(-1)^i/prime(i),1)) /* _Michael Somos_, Feb 01 2004 */
%K nonn
%O 1,3
%A _Clark Kimberling_