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A078782
Nonprimes (A018252) with prime (A000040) subscripts.
15
4, 6, 9, 12, 18, 21, 26, 28, 34, 42, 45, 52, 57, 60, 65, 74, 81, 84, 91, 95, 98, 106, 112, 119, 128, 133, 135, 141, 143, 147, 165, 170, 177, 180, 192, 195, 203, 209, 214, 220, 228, 231, 244, 246, 250, 253, 267, 284, 288, 290, 295, 301, 303, 316, 323, 329, 336
OFFSET
1,1
COMMENTS
a(n) = A018252(A000040(n)). Subsequence of A175250 (nonprimes (A018252) with noncomposite (A008578) subscripts), a(n) = A175250(n+1). a(n) U A102615(n) = A018252(n). [From Jaroslav Krizek, Mar 13 2010]
EXAMPLE
a(4) = nonprime(prime(4)) = nonprime(7) = 12.
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: A310670 A088765 A175250 * A165897 A020165 A368196
KEYWORD
easy,nonn
AUTHOR
Joseph L. Pe, Jan 09 2003
EXTENSIONS
Corrected by Jaroslav Krizek, Mar 13 2010
STATUS
approved