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A309572
Number of primes of which all substrings in base n are primes.
1
0, 1, 3, 5, 5, 7, 19, 7, 9, 6, 25, 11, 22, 16, 18, 12, 54, 12, 48, 18, 33, 13, 103, 16, 27, 20, 50, 13, 161, 14, 66, 27, 47, 19, 109, 18, 67, 22, 70, 15, 226, 22, 82, 33, 67, 24, 261, 26, 137, 29, 89, 23, 273, 29, 102, 31, 82, 24, 546, 26, 119, 37, 110, 29
OFFSET
2,3
LINKS
Rémy Sigrist, Table of n, a(n) for n = 2..2500 (first 199 terms from Lucas H. Gabrielli)
EXAMPLE
For base 10, there are 9 primes whose substrings are also primes: 2, 3, 5, 7, 23, 37, 53, 73, and 373, thus a(10) = 9.
PROG
(PARI) See Links section.
CROSSREFS
Cf. A245277.
Sequence in context: A090941 A090917 A226540 * A366679 A296107 A158331
KEYWORD
base,nonn
AUTHOR
Lucas H. Gabrielli, Aug 08 2019
STATUS
approved