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A175248
Noncomposites (A008578) with noncomposite (A008578) subscripts.
0
1, 2, 3, 7, 13, 29, 37, 53, 61, 79, 107, 113, 151, 173, 181, 199, 239, 271, 281, 317, 349, 359, 397, 421, 457, 503, 541, 557, 577, 593, 613, 701, 733, 769, 787, 857, 863, 911, 953, 983, 1021, 1061, 1069, 1151, 1163, 1193, 1213, 1291, 1399, 1429, 1439, 1459
OFFSET
1,2
COMMENTS
Noncomposite numbers of order 2.
a(n) = noncomposite(noncomposite(n)) = A008578(A008578(n)). a(1) = 1, a(n) = A055003(n) for n >=2. a(n) U A175249(n+1) = A008578 for n >= 1.
FORMULA
a(n)=A008578(A008578(n)).
EXAMPLE
a(5) = 13 because a(5) = q(q(5)) = q(7) = 13, q = noncomposite.
CROSSREFS
Sequence in context: A074129 A233042 A055003 * A099361 A234003 A233350
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Mar 13 2010
EXTENSIONS
More terms from Juri-Stepan Gerasimov, Apr 15 2010
Edited by N. J. A. Sloane, Apr 21 2010 at the suggestion of R. J. Mathar
STATUS
approved