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A116616
Values of n such that prime(2n+1) mod 12 = 7.
1
5, 9, 13, 15, 23, 30, 31, 33, 36, 37, 42, 46, 47, 49, 50, 52, 55, 57, 58, 62, 64, 65, 66, 70, 71, 74, 76, 77, 78, 81, 83, 87, 88, 89, 90, 96, 103, 106, 108, 114, 116, 117, 121, 123, 124, 130, 134, 142, 144, 148, 151, 152, 160, 163, 166, 167, 175, 182, 185, 191, 192
OFFSET
1,1
LINKS
FORMULA
Equals { odd terms in A160592 = A000720(A068229) } / 2, rounded towards zero. - M. F. Hasler, May 22 2009
EXAMPLE
33 is in the sequence because the 67th prime is 331 and 331 mod 12=7.
MAPLE
a:=proc(n) if ithprime(2*n+1) mod 12 = 7 then n else fi end: seq(a(n), n=0..215);
MATHEMATICA
Select[Range[220], Mod[Prime[2# + 1], 12] == 7 &] (* Stefan Steinerberger, Apr 08 2006 *)
PROG
(PARI) for(n=1, 999, prime(2*n+1)%12==7 & print1(n", ")) \\ M. F. Hasler, May 22 2009
CROSSREFS
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Mar 29 2006
EXTENSIONS
Edited by N. J. A. Sloane, Apr 05 2006
STATUS
approved