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A113767 Values of the exponents in A084435. 1
0, 1, 2, 1, 5, 1, 1, 29, 3, 37, 31, 227, 835, 115, 7615, 6071, 218431 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
If A084435 ever hits a Sierpinski number, the sequence is finite.
a(18) > 10^5. - Harsh R. Aggarwal, Apr 11 2018
LINKS
Eric Weisstein's World of Mathematics, Sierpinski Number of the Second Kind.
PROG
(PARI) a=2; for(x=1, 16, for(k=0, 1000000, p=2^k*a+1; if(isprime(p), print(k); break)); a=p)
CROSSREFS
Sequence in context: A323954 A143983 A282988 * A352566 A246964 A157334
KEYWORD
nonn,hard,more
AUTHOR
Ken Takusagawa, Jan 19 2006
EXTENSIONS
a(16)-a(17) from Harsh R. Aggarwal, Apr 11 2018
STATUS
approved

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Last modified April 19 19:02 EDT 2024. Contains 371798 sequences. (Running on oeis4.)