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A060568
Number of primes between n and R(n) where R(n) (A004086) is the digit reversal of n.
1
0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 3, 4, 6, 9, 11, 12, 15, 16, 7, 3, 0, 2, 4, 6, 9, 11, 13, 14, 8, 4, 2, 0, 2, 4, 7, 8, 10, 12, 10, 6, 4, 2, 0, 2, 4, 6, 8, 9, 12, 9, 6, 4, 2, 0, 2, 5, 7, 7, 14, 11, 9, 7, 4, 2, 0, 2, 4, 5, 15, 12, 11, 8, 6, 5, 2, 0, 2, 2, 18, 15, 13, 10, 8, 7, 4, 2, 0, 1, 20, 16, 14
OFFSET
1,10
EXAMPLE
a(10) = 4, as there are four primes between 10 and 1.
CROSSREFS
Sequence in context: A106142 A376994 A092512 * A073466 A062525 A085655
KEYWORD
nonn,base,easy
AUTHOR
Amarnath Murthy, Apr 27 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), May 10 2001
STATUS
approved