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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
OFFSET
1,1
COMMENTS
The prime/nonprime compound sequence ABB. - N. J. A. Sloane, Apr 06 2016
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 * A365235 A290163 A284496
KEYWORD
nonn
AUTHOR
Cino Hilliard, Jan 31 2005
EXTENSIONS
Edited by Robert G. Wilson v, Feb 04 2005
STATUS
approved