A056915 Strong pseudoprimes to bases 2, 3 and 5, i.e., intersection of A001262, A020229, and A020231.

25326001, 161304001, 960946321, 1157839381, 3215031751, 3697278427, 5764643587, 6770862367, 14386156093, 15579919981, 18459366157, 19887974881, 21276028621, 27716349961, 29118033181, 37131467521, 41752650241, 42550716781, 43536545821

Offset

1,1

Comments

These first 13 numbers are the only ones less than 25*10^9 which are simultaneously strong pseudoprimes to bases 2, 3 and 5. Taken from the same table - which indicates (only) whether they are also strong pseudoprime (spsp) or pseudoprime (psp) to base 7, 11 and/or 13: 161304001 is spsp to 11; 3215031751 is spsp to base 7 and is psp to both bases 11 and 13; 5764643587 is spsp to base 13; 14386156093 is psp to bases 7, 11 and 13. 15579919981 is psp to base 7 and spsp to base 11; 19887974881 is psp to base 7; and 21276028621 is psp to bases 11 and 13.

References

P. Ribenboim, The Little Book of Big Primes. Springer-Verlag, NY, 1991, pp. 82-83.

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Pomerance, C., Selfridge, J.L. and Wagstaff, Jr., S.S. The pseudoprimes to 25*10^9, Mathematics of Computation 35, 1980, pp. 1003-1026.

Eric Weisstein's World of Mathematics, Strong Pseudoprime

Index entries for sequences related to pseudoprimes

Crossrefs

Cf. A072276, A001262, A020229, A020231, superset of A074773.

Sequence in context: A175580 A204778 A172795 * A233448 A112130 A334373

Adjacent sequences: A056912 A056913 A056914 * A056916 A056917 A056918

Keyword

nice,nonn

Author

Rick L. Shepherd, Feb 12 2002

Extensions

B-file and more terms from Charles R Greathouse IV, Aug 14 2010

Status

approved