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A062568
a(n) is the smallest n-digit strong pseudoprime (in base 2).
9
2047, 15841, 104653, 1004653, 10323769, 100463443, 1002261781, 10000321321, 100004790097, 1000002977551, 10000130243671, 100002236680837, 1000003918690669, 10000008250001701, 100000150553089531, 1000000274500018837, 10000003599249373469
OFFSET
4,1
EXAMPLE
a(1)=2047 because 2047 is the smallest 4-digit strong pseudoprime to base 2.
CROSSREFS
KEYWORD
hard,base,nonn
AUTHOR
Shyam Sunder Gupta, Feb 13 2002
EXTENSIONS
Edited by Charles R Greathouse IV, Nov 01 2009
a(17)-a(20) from Charles R Greathouse IV, Mar 14 2011
STATUS
approved