%I A128288
%S A128288 3,13,37,43,53,67,83,107,157,163,173,197,227,277,283,293,307,317,347,
%T A128288 373,397,443,467,523,547,557,563,587,613,643,653,677,683,733,757,773,
%U A128288 787,797,827,853,877,883,907,947,997,1013,1093,1117,1123,1163,1187,1213
%N A128288 A023163(n)/3 for n>1.
%C A128288 3 divides A023163(n) for n>1. A023163(n) are the numbers n such that 
               Fib(n) == -2 (mod n). Almost all terms of a(n) are prime that belong 
               to A003631 = {2, 3, 7, 13, 17, 23, 37, 43, 47, 53, 67, 73, 83, 97} 
               Primes congruent to {2, 3} mod 5; that are also the primes p that 
               divide Fibonacci(p+1). The first composite term is a(74) = 1853 = 
               17*109. The second composite term is 9701 = 89*109. The third composite 
               term is 10877 = 73*149 belong to A069107(n) Composite n such that 
               n divides F(n+1) where F(k) are the Fibonacci numbers. Composite 
               terms in a(n) are listed in A128289 = {1853, 9701, 10877, 17261, 
               ...}.
%F A128288 a(n) = A023163(n)/3 for n>1.
%e A128288 A023163(n) begins {1, 9, 39, 111, 129, 159, 201, 249, 321, 471, 489, 
               519, ...}.
%e A128288 Thus a(2) = A023163(2)/3 = 9/3 = 3, a(3) = A023163(3)/3 = 39/3 = 13.
%Y A128288 Cf. A002708, A023172, A023173, A023162, A023163 = numbers n such that 
               Fib(n) == -2 (mod n). Cf. A003631, A069107, A128289 = Composite terms 
               in A128288.
%Y A128288 Sequence in context: A146424 A146049 A061483 this_sequence A113115 A107136 
               A153009
%Y A128288 Adjacent sequences: A128285 A128286 A128287 this_sequence A128289 A128290 
               A128291
%K A128288 nonn
%O A128288 2,1
%A A128288 Alexander Adamchuk (alex(AT)kolmogorov.com), Feb 24 2007