A244566 - OEIS

%I #21 Jun 15 2015 02:29:14

%S 327739,5455789,8879993,9043831,21823667,25763447,29949559,75037639,

%T 92732027,119863547,119879899,122091961,146880319,151060223,152106751,

%U 163378771,181339441,182384417,182646049,218039041,232190537

%N Odd integers n such that for every integer k>0, n*2^k+1 has a divisor in the set { 3, 5, 7, 13, 17, 97, 257 }.

%C These are the Sierpiński numbers (A076336) with covering set {3, 5, 7, 13, 17, 97, 257}. - _David W. Wilson_, Jul 18 2014

%C For n > 96, a(n) = a(n-96) + 1156954890, the first 96 values are in the table.

%H Pierre CAMI, <a href="/A244566/b244566.txt">Table of n, a(n) for n = 1..96</a>

%F For n > 96, a(n) = a(n-96) + 1156954890.

%o (PARI) is(n)=my(G=578477445,t=Mod(n,G)); for(k=1,768,t*=2; if(gcd(t+1, G)==1, return(0))); n%2 \\ _Charles R Greathouse IV_, Jul 18 2014

%Y Cf. A076336, A244076, A244561, A244562, A244563, A244564, A244565.

%K nonn,easy

%O 1,1

%A _Pierre CAMI_, Jun 30 2014