A060270 Distance of n-th primorial from previous prime.

1, 1, 11, 1, 1, 29, 23, 43, 41, 73, 59, 1, 89, 67, 73, 107, 89, 101, 127, 97, 83, 89, 1, 251, 131, 113, 151, 263, 251, 223, 179, 389, 281, 151, 197, 173, 239, 233, 191, 223, 223, 293, 593, 293, 457, 227, 311, 373, 257, 307, 313, 607, 347, 317, 307, 677, 467, 317

Offset: 2

Author

Labos Elemer, Mar 23 2001

Keywords

• nonn

Examples

			Before 7th primorial 510481 is the largest prime. Its distance from 510510 is a(7)=29.
		

Links

• Robert G. Wilson v, Table of n, a(n) for n = 2..1000

Crossrefs

Cf. A002110, A038710, A007014, A058044, A038711, A055211.

Programs

Maple

[seq(product(ithprime(j),j=1..n)-prevprime(product(ithprime(j),j=1..n)), n=2..50)];

Mathematica

Map[# - NextPrime[#, -1] &, Rest@ FoldList[Times, Prime@ Range[59]]] (* Michael De Vlieger, Aug 10 2023 *)

PARI

a(n) = my(P=vecprod(primes(n))); P-precprime(P-1); \\ Michel Marcus, Aug 11 2023

Formula

a(n)=1 for n=2, 3, 5, 6, 13, 24, 66, 68, 167, ... (A057704); a(n)=A055211(n) otherwise. - Jeppe Stig Nielsen, Oct 31 2003

Extensions

More terms from Jeppe Stig Nielsen, Oct 31 2003