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A074773
Strong pseudoprimes to bases 2, 3, 5 and 7.
11
3215031751, 118670087467, 307768373641, 315962312077, 354864744877, 457453568161, 528929554561, 546348519181, 602248359169, 1362242655901, 1871186716981, 2152302898747, 2273312197621, 2366338900801, 3343433905957, 3461715915661, 3474749660383, 3477707481751, 4341937413061, 4777422165601, 5537838510751
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
G. Jaeschke, On strong pseudoprimes to several bases, Mathematics of Computation, 61 (1993), 915-926.
Eric Weisstein's World of Mathematics, Miller's Primality Test
PROG
(PARI) sprp(n, b)=my(s=valuation(n-1, 2), d=Mod(b, n)^(n>>s)); if(d==1, return(1)); for(i=1, s-1, if(d==-1, return(1)); d=d^2; ); d==-1
is(n)=sprp(n, 2) && sprp(n, 3) && sprp(n, 5) && sprp(n, 7) && !isprime(n) \\ Charles R Greathouse IV, Sep 14 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Don Reble, Sep 07 2002
EXTENSIONS
b-file, link, and editing from Charles R Greathouse IV, Aug 14 2010
STATUS
approved