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A039994
Number of primes embedded in decimal expansion of prime(n) as substrings.
2
1, 1, 1, 1, 1, 2, 2, 1, 3, 2, 2, 3, 1, 2, 2, 3, 2, 1, 2, 2, 3, 2, 2, 1, 2, 2, 3, 3, 2, 4, 4, 5, 6, 4, 2, 3, 4, 3, 4, 6, 5, 2, 3, 4, 5, 2, 3, 4, 3, 3, 4, 5, 3, 3, 4, 4, 3, 4, 3, 2, 5, 5, 4, 4, 4, 6, 3, 4, 5, 2, 4, 4, 5, 5, 5, 3, 3, 5, 2, 1, 3, 3, 5, 3, 3, 3, 1, 4, 3, 3, 4, 4, 3, 2, 1, 4, 3, 3, 6, 3, 4, 3, 4, 3, 4
OFFSET
1,6
FORMULA
a(n) = A039995(prime(n)).
EXAMPLE
a(26) = 2 since prime(26) = 101 and "101" has two prime subsequences, 101 and 11.
CROSSREFS
Cf. A039995.
Different from A039996.
Sequence in context: A111709 A348911 A039996 * A348485 A343188 A326394
KEYWORD
nonn,base
EXTENSIONS
Definition and example clarified by N. J. A. Sloane, Jun 03 2024
STATUS
approved