A074813 Number of primes between n and R(n) (inclusive), where R(n) (A004086) is the digit reversal of n.
0, 1, 1, 0, 1, 0, 1, 0, 0, 4, 1, 3, 6, 7, 9, 12, 14, 15, 17, 8, 3, 0, 3, 4, 6, 9, 11, 13, 15, 9, 6, 3, 0, 3, 5, 7, 10, 11, 12, 10, 7, 4, 3, 0, 2, 4, 7, 8, 9, 13, 9, 6, 5, 2, 0, 2, 5, 7, 8, 14, 12, 9, 7, 4, 2, 0, 3, 4, 5, 16, 14, 11, 10, 7, 5, 3, 0, 2, 4, 18, 15, 13, 11, 8, 7, 4, 2, 0, 2, 20, 17
Offset: 1
Examples
The primes between n = 13 and 31, inclusive, are 13, 17, 19, 23, 29, 31; so a(13) = 6.
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