OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..240
Thomas R. Nicely, First occurrence prime gaps [For local copy see A000101]
FORMULA
a(n) = A000230(3n).
EXAMPLE
d = 72 appears after 31397, while smaller d = 54, 60, 66 come later, following primes 35617, 43331, 162143, respectively.
MATHEMATICA
Module[{nn=32*10^5, prs, gps}, prs=Prime[Range[nn]]; gps=Differences[prs]; Table[SelectFirst[Thread[{Most[prs], gps}], #[[2]]==6n&], {n, 30}]][[;; , 1]] (* Harvey P. Dale, Mar 03 2025 *)
PROG
(PARI) a(n) = {p=3; q = nextprime(p+1); while((q-p) != 6*n, p = q; q = nextprime(q+1)); p; } \\ Michel Marcus, Mar 12 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 28 2000
EXTENSIONS
Offset corrected by M. F. Hasler, Apr 09 2013
STATUS
approved
