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A102616 Nonprime numbers of order 3. 3
1, 14, 16, 22, 24, 25, 30, 33, 35, 36, 39, 44, 46, 48, 50, 51, 54, 55, 56, 62, 64, 66, 68, 69, 70, 75, 76, 77, 80, 85, 86, 87, 90, 92, 93, 94, 96, 100, 102, 104, 105, 108, 111, 115, 116, 117, 118, 120, 122, 123, 124, 126, 130, 132, 134, 136, 138, 142, 144, 145, 148, 150 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

nps(n,1) -> list nonprime(n) or the sequence of nonprime numbers. nps(n,2) -> list nonprime(nonprime(n)) or nps of order 2. nps(n,3) -> list nonprime(nonprime(nonprime(n))) or npcs of order 3 ..... The order is the number of nestings - 1.

LINKS

Table of n, a(n) for n=1..62.

EXAMPLE

Nonprime(2) = 4.

Nonprime(4) = 8.

Nonprime(8) = 14, the 2nd 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_] := FixedPoint[n + PrimePi[ # ] &, n]; Nest[ nonPrime, Range[62], 3] (* Robert G. Wilson v, Feb 04 2005)

PROG

(PARI) \We perform nesting(s) with a loop. cics(n, m) = { local(x, y, z); for(x=1, n, z=x; for(y=1, m+1, z=composite(z); ); print1(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

Cf. A018252, A102615.

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: A076055 A068653 A225193 * A291907 A255846 A076023

Adjacent sequences:  A102613 A102614 A102615 * A102617 A102618 A102619

KEYWORD

nonn

AUTHOR

Cino Hilliard, Jan 31 2005

EXTENSIONS

Edited by Robert G. Wilson v, Feb 04 2005

STATUS

approved

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Last modified November 15 08:58 EST 2019. Contains 329144 sequences. (Running on oeis4.)