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A286711
a(n) is the position of the first occurrence of 2n as a local minimum in the prime gaps (A001223).
1
5, 22, 67, 126, 138, 1253, 1586, 1356, 3524, 2129, 10464, 14174, 19633, 23354, 44754, 52872, 194426, 122046, 209609, 249329, 256005, 493543, 335001, 116305, 895479, 1698315, 1324483, 2783617, 679305, 1015023, 2217824, 3625328, 1595431, 6660573, 13611829, 4061952, 14641489
OFFSET
1,1
LINKS
Zak Seidov and Giovanni Resta, Table of n, a(n) for n = 1..100 (first 50 terms from Zak Seidov)
EXAMPLE
a(1)=5 because A001223(4)=4, A001223(5)=2, A001223(6)=4,
a(2)=22 because A001223(21)=6, A001223(22)=4, A001223(23)=6,
a(50)=112849562 because A001223(112849561)=108, A001223(112849562)=100, A001223(112849563)=120,
MATHEMATICA
nv=tg=20; T = 0 Range[nv]; n=0; p=q=3; b=c=2; While[tg>0, p = NextPrime[p]; n++; {a, b, c, q} = {b, c, p-q, p}; If[b <= 2 nv && a>b<c && T[[b/2]] == 0, T[[b/2]] = n; tg--]]; T (* Giovanni Resta, May 13 2017 *)
CROSSREFS
Cf. A001223 (differences between consecutive primes), A196175 (positions of local minima in A001223).
Sequence in context: A064836 A273311 A288534 * A222632 A366081 A273336
KEYWORD
nonn
AUTHOR
Zak Seidov, May 13 2017
STATUS
approved