OFFSET
1,5
COMMENTS
Subsidiary sequences: (set(1)) Index of the start of the first occurrence of a string of n consecutive 1's or 2's or 3's etc. (set (2)): a(n) = smallest prime such that concatenation of 1 with n successive primes starting from a(n) gives primes in each case. (n primes are obtained.) Similarly for 2, 3, etc. Conjecture: The subsidiary sequences are infinite.
A065112(n) = a(n) concatenated with prime(n). - Bill McEachen, May 27 2021
PROG
(PARI) a(n) = if ((n==1) || (n==3), 0, my(k=1); while (!isprime(eval(Str(k, prime(n)))), k++); k); \\ Michel Marcus, Jul 11 2021
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Oct 15 2003
EXTENSIONS
More terms from Ray Chandler, Oct 18 2003
STATUS
approved