The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A102617 Primes p(n) such that n is a second-order nonprime number. 12
 2, 19, 29, 43, 47, 53, 71, 79, 89, 97, 103, 113, 131, 137, 149, 151, 163, 167, 173, 193, 199, 223, 227, 229, 233, 251, 257, 263, 271, 293, 307, 311, 317, 337, 347, 349, 359, 379, 383, 389, 397, 409, 421, 439, 443, 449, 457, 463, 479, 487, 491, 503, 523, 541 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The prime/nonprime compound sequence ABB. - N. J. A. Sloane, Apr 06 2016 LINKS EXAMPLE Nonprime(4) = 8. The 8th prime is 19, the second entry. MAPLE For Maple code for the prime/nonprime compound sequences (listed in cross-references) see A003622. - N. J. A. Sloane, Mar 30 2016 MATHEMATICA nonPrime[n_Integer] := FixedPoint[n + PrimePi[ # ] &, n]; Prime /@ nonPrime /@ nonPrime /@ Range[54] (* Robert G. Wilson v, Feb 04 2005 *) PROG (PARI) \We perform nesting(s) with a loop. cips(n, m) = { local(x, y, z); for(x=1, n, z=x; for(y=1, m+1, z=composite(z); ); print1(prime(z)", ") ) } composite(n) = \ The n-th composite number. 1 is defined as a composite number. { local(c, x); c=1; x=0; while(c <= n, x++; if(!isprime(x), c++); ); return(x) } CROSSREFS Let A = primes A000040, B = nonprimes A018252. The 2-level compounds are AA = A006450, AB = A007821, BA = A078782, BB = A102615. The 3-level compounds AAA, AAB, ..., BBB are A038580, A049078, A270792, A102617, A270794, A270796, A102216. Sequence in context: A186682 A031030 A083689 * A290163 A284496 A120276 Adjacent sequences:  A102614 A102615 A102616 * A102618 A102619 A102620 KEYWORD nonn AUTHOR Cino Hilliard, Jan 31 2005 EXTENSIONS Edited by Robert G. Wilson v, Feb 04 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified April 16 07:59 EDT 2021. Contains 343030 sequences. (Running on oeis4.)