OFFSET
1,1
COMMENTS
Except for the first term, all a(n)=13 (mod 72) with x=3 (mod 6). The lesser of the twin prime pair is given by A253639, the x-values in A086381. - M. F. Hasler, Jan 18 2015
LINKS
M. F. Hasler, Table of n, a(n) for n = 1..3044 (all terms below 10^12).
FORMULA
MATHEMATICA
Transpose[Select[Table[x^2+{2, 4}, {x, 5000}], AllTrue[#, PrimeQ]&]][[2]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 15 2015 *)
PROG
write(f="b085554.txt", c=1, " 5"); forstep(x=3, 1e6, 6, is_A086381(x)&&write(f, c++" "x^2+4))
\\ M. F. Hasler, Jan 18 2015
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Jul 04 2003
EXTENSIONS
Edited by Don Reble, May 03 2006
Definition corrected by Harvey P. Dale and Franklin T. Adams-Watters, Jan 15 2015
STATUS
approved