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A103964
Record values in A040076.
8
0, 1, 2, 3, 6, 8, 583, 6393, 9715, 33288, 3321063, 5054502, 31172165
OFFSET
1,3
COMMENTS
The index sequence of this sequence is 1, 3, 7, 17, 19, 31, 47, 383, 2897. A040076(2897)>8192, not yet found.
A064699 gives where the records occur.
EXAMPLE
A040076(1)=0, so a(1)=0;
A040076(3)=1, so a(2)=1;
MATHEMATICA
k = -1; n = 0; km = k; While[k < 8192, n++; k = 0; cp = n*(2^ k) + 1; While[(! PrimeQ[cp]) && (k < 8192), k++; cp = n*(2^k) + 1]; If[k > km, km = k; Print[{n, km}]]]
CROSSREFS
Sequence in context: A187026 A179221 A350119 * A199790 A088329 A193079
KEYWORD
nonn,more
AUTHOR
Lei Zhou, Feb 24 2005
EXTENSIONS
Extended by T. D. Noe, Nov 15 2010
a(13) was found by PrimeGrid, added by Richard N. Smith, Jul 15 2019
STATUS
approved