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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).
2
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
1,3
FORMULA
a(n)=Min{x : A073131[x]=2n}
EXAMPLE
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.
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
CROSSREFS
Sequence in context: A319903 A135076 A155546 * A294075 A165355 A038004
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 16 2002
EXTENSIONS
Edited by Robert G. Wilson v, Jul 17 2002
STATUS
approved