Search: id:A000355 Results 1-1 of 1 results found. %I A000355 %S A000355 3,11,23,29,83,89,131,191,251,431,443,491,509,683,743,809,911,1031,1049, %T A000355 1103,1223,1229,1289,1409,1451,1511,1583,1811,1889,1931,2003,2063,2069, %U A000355 2129,2351,2543,2549,2903,2963,2969,3023,3329,3389,3449,3491,3623,3803 %N A000355 Primes == 3, 9, 11 (mod 20) such that 2p+1 is also prime. %C A000355 a(n) = (A000353(n)-1)/2; [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Feb 10 2009] %D A000355 R. A. J. Matthews, Maximally periodic reciprocals, Bull. Instititute of Mathematics and Its Applications, vol. 28, p. 147-148, 1992. %H A000355 R. Zumkeller, Table of n, a(n) for n = 1..1000 [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Feb 10 2009] %Y A000355 Subset of A005384. %Y A000355 Sequence in context: A087078 A141226 A049491 this_sequence A163769 A100860 A018630 %Y A000355 Adjacent sequences: A000352 A000353 A000354 this_sequence A000356 A000357 A000358 %K A000355 nonn %O A000355 1,1 %A A000355 R. A. J. Matthews [ 100265.3005(AT)compuserve.com ] %E A000355 More terms from Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Feb 10 2009 Search completed in 0.001 seconds