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A102738
Numbers k such that 4*10^k - 11 is prime.
0
1, 2, 3, 4, 5, 15, 35, 61, 256, 357, 628, 767, 1064, 1096, 6608, 14821, 15341, 18795, 22648, 24199, 31919, 38519, 44279
OFFSET
1,2
COMMENTS
Numbers corresponding to terms <= 767 are certified primes. - Klaus Brockhaus, Feb 16 2005
The next term is larger than 2500. - Stefan Steinerberger, Feb 18 2006
MATHEMATICA
For[n=1, n<2500, n++, If[PrimeQ[4*10^n-11], Print[n]]] (* Stefan Steinerberger, Feb 18 2006 *)
PROG
(PARI) is(n)=ispseudoprime(4*10^n-11) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A145029 A145030 A242948 * A098553 A132705 A177334
KEYWORD
more,nonn
AUTHOR
Tom Mueller (muel4503(AT)uni-trier.de), Feb 08 2005
EXTENSIONS
a(9)-a(14) from Klaus Brockhaus, Feb 16 2005
a(15) from Ryan Propper, Jul 21 2006
a(16)-a(17) from Michael S. Branicky, May 01 2023
a(18)-a(23) from Kamada data by Tyler Busby, May 03 2024
STATUS
approved