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A068445 Palindromic pseudoprimes (base 2). 0
101101, 129921, 1837381, 127665878878566721, 1037998220228997301 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(6), if it exists, is greater than 2^64. - Charles R Greathouse IV, Jun 29 2011

LINKS

Table of n, a(n) for n=1..5.

Patrick De Geest, Palindromic Pseudoprimes (base 2)

Carlos Rivera, Puzzle 170

EXAMPLE

a(2)= 129921, So the 2nd palindromic pseudoprime(base-2) number is 129921.

CROSSREFS

Sequence in context: A210895 A107274 A107276 * A210888 A115828 A168529

Adjacent sequences:  A068442 A068443 A068444 * A068446 A068447 A068448

KEYWORD

hard,more,nice,base,nonn

AUTHOR

Shyam Sunder Gupta, Mar 10 2002; extended Oct 20 2002

STATUS

approved

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Last modified January 19 15:37 EST 2020. Contains 331049 sequences. (Running on oeis4.)