A258095 Numbers m, such that the smallest prime factor of 1+78557*2^m doesn't belong to the covering set {3, 5, 7, 13, 19, 37, 73}.

39, 183, 219, 1047, 1227, 1299, 1875, 2271, 2559, 2703, 3315, 3531, 3819, 4359, 5079, 5187, 5403, 6015, 6339, 6447, 6843, 7491, 7599, 7671, 8499, 8535, 8859, 9327, 9579, 10119, 10155, 10623, 10983, 11379, 11667, 11811, 12639, 12711, 13467, 13755, 13899

Offset

1,1

Comments

A258091(a(n)) < 73, as each term in A258073 has at least one prime factor in the covering set.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..250

Wikipedia, Sierpinski Number

Wikipedia, Covering set

Example

a(1) = 39; A258073(39) = 43187167471599617 = 71 * 73 * 211 * 39490356709, and 71 is not an element of the covering set.

Prog

(Haskell)
a258095 n = a258095_list !! (n-1)
a258095_list = filter
               (\x -> a258091 x `notElem` [3, 5, 7, 13, 19, 37, 73]) [1..]

Crossrefs

Cf. A258073, A258091, A020639.

Sequence in context: A251328 A235981 A235974 * A193228 A243578 A124619

Adjacent sequences: A258092 A258093 A258094 * A258096 A258097 A258098

Keyword

nonn

Author

Reinhard Zumkeller, May 19 2015

Status

approved