A217892 Indices of records in A194591.

1, 5, 13, 47, 59, 109, 241, 335, 1109, 1373, 1447, 14893, 37892, 56543, 185644, 649603, 838441, 8840101, 16935761, 100604513, 118373279, 270704167, 1355477231

Offset

1,2

Comments

Record values are given by A194600.

Links

Table of n, a(n) for n=1..23.

Mathematica

a[n_]:= (k=0; While[!PrimeQ[n*2^k-1] && !PrimeQ[n*2^k+1], k++]; k); w = {1}; v = {0}; Do[If[a[n]>v[[-1]], AppendTo[v, a[n]]; Print[n]], {n, 1356000000}] (* Farideh Firoozbakht, Oct 16 2014 *)

Crossrefs

Cf. A194635, A194639

Sequence in context: A320877 A099972 A060050 * A194639 A152925 A304964

Adjacent sequences: A217889 A217890 A217891 * A217893 A217894 A217895

Keyword

more,nonn

Author

Max Alekseyev, Oct 14 2012

Extensions

a(23)=A194639(22) from Wilfrid Keller, added by Max Alekseyev, Oct 18 2014

Status

approved