Number of composite numbers around 5^n.
0, 5, 13, 11, 15, 9, 15, 65, 41, 9, 25, 69, 57, 13, 45, 85, 17, 113, 71, 73, 77, 71, 73, 95, 77, 13, 49, 75, 77, 129, 109, 285, 163, 169, 423, 153, 69, 131, 335, 161, 159, 89, 399, 341, 143, 35, 207, 107, 283, 97, 137, 215, 19, 65, 131, 503, 319, 119, 353, 399
1
T. D. Noe, Plot of 1000 terms
T. D. Noe, Table of 1000 terms
(Mma) Join[{0}, Table[NextPrime[5^n] - NextPrime[5^n, -1] - 1, {n, 2, 50}]]
nonn
T. D. Noe, Mar 09 2015