The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A224856 Numbers n such that 90*n + 29 and 90*n + 31 are twin primes. 1
 0, 6, 7, 11, 14, 28, 30, 33, 37, 39, 47, 53, 61, 65, 74, 75, 76, 77, 84, 88, 91, 110, 128, 139, 152, 158, 170, 179, 180, 194, 195, 201, 215, 216, 228, 229, 251, 271, 282, 305, 308, 312, 334, 336, 345, 362, 366, 368, 370, 373, 383, 384, 410, 411, 413, 427, 450 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA A201739 INTERSECT A201819. MAPLE a:= proc(n) option remember; local k; for k from 1+        `if`(n=1, -1, a(n-1)) while not (isprime(29+(90*k))         and isprime(31+(90*k))) do od; k     end: seq(a(n), n=1..100);  # Alois P. Heinz, Jul 23 2013 MATHEMATICA Select[Range[0, 499], PrimeQ[90# + 29] && PrimeQ[90# + 31] &] (* copied from: Alonso del Arte, Jul 22 2013 *) CROSSREFS Cf. A201739, A201819. Sequence in context: A190612 A270431 A315832 * A182156 A166496 A267413 Adjacent sequences:  A224853 A224854 A224855 * A224857 A224858 A224859 KEYWORD nonn,easy AUTHOR J. W. Helkenberg, Jul 22 2013 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 28 19:16 EDT 2021. Contains 347717 sequences. (Running on oeis4.)