A352002 a(n) = prime(n)# + prime(n), where prime(n)# is the n-th primorial number A002110(n).

4, 9, 35, 217, 2321, 30043, 510527, 9699709, 223092893, 6469693259, 200560490161, 7420738134847, 304250263527251, 13082761331670073, 614889782588491457, 32589158477190044783, 1922760350154212639129, 117288381359406970983331, 7858321551080267055879157, 557940830126698960967415461

Offset: 1

Author

Ryan Bresler, Feb 27 2022

Keywords

• nonn

Examples

			a(3) = prime(3)# + prime(3) = 2 * 3 * 5 + 5 = 35.
		

Crossrefs

Cf. A000040, A002110.

Programs

PARI

a(n) = prime(n) + prod(k=1, n, prime(k)); \\ Michel Marcus, Feb 28 2022

Python

from sympy import primorial, prime
def a(n): return primorial(n) + prime(n)
for n in range(1,50):
    print(a(n), end=", ") # Javier Rivera Romeu, Mar 01 2022

Formula

a(n) = A002110(n) + A000040(n). Also a(n) = prime(n) * (prime(n-1)# + 1).