A073132 Smallest subscript j such that d=p[p(j+1)]-p[p(j)]=2n, or 0 if j does not exist (at d=4).

1, 0, 2, 7, 5, 13, 4, 8, 6, 14, 12, 27, 9, 51, 11, 40, 21, 16, 25, 39, 36, 96, 58, 18, 132, 134, 56, 106, 108, 72, 34, 102, 42, 158, 202, 68, 53, 118, 121, 46, 124, 101, 383, 91, 157, 30, 80, 97, 204, 126, 258, 139, 381, 145, 222, 47, 62, 240, 242, 363, 66, 177, 565

Offset: 1

Author

Labos Elemer, Jul 16 2002

Keywords

• nonn

Examples

			d=20 appears first at n=14, p(15)=47,p(14)=43, d=p(47)-p(43)=211-191=20, so a(20/2)=a(10)=14.
		

Crossrefs

Cf. A073130, A073131.

Programs

Mathematica

t=Table[0, {100}]; Do[s = Prime[ Prime[x+1]] - Prime[ Prime[x]]; If[ s < 202 && t[[s/2]]==0, t[[s/2]]=n], {n, 1, 1000}]; t

Formula

a(n)=Min{x : A073131[x]=2n}

Extensions

Edited by Robert G. Wilson v, Jul 17 2002