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A263875
a(n) = least positive k such that A263874(n) + 2^k is prime.
3
1, 2, 3, 4, 5, 8, 10, 20, 29, 955, 4583176, 9092392
OFFSET
1,2
COMMENTS
A263874 gives where the records occur.
PROG
(PARI) a=1; forstep(n=1, 773, 2, k=1; while(!ispseudoprime(n+2^k), k++); if(k+1>a, print1(k, ", "); a=k+1));
CROSSREFS
Sequence in context: A222297 A211981 A019997 * A351702 A125157 A093327
KEYWORD
nonn,hard,more
AUTHOR
STATUS
approved