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A121061 Numbers n such that n-th partition number A000041(n) is a 3-almost prime (A014612). 0
9, 10, 16, 18, 20, 22, 25, 29, 31, 34, 37, 42, 45, 48, 50, 56, 57, 60, 63, 69, 71, 72, 73, 83, 85, 91, 101, 102, 112, 113, 114, 119, 139, 144, 148, 151, 155, 156, 172, 175, 183, 185, 190, 192, 195, 202, 208, 217, 238, 242, 244, 245, 247, 256, 257, 272, 275, 291, 293 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
3-almost prime analog of: A046063 Numbers n such that n-th partition number A000041(n) is prime; A065729 n-th partition number (A000041[n]) is a semiprime. See also A065728 Partition numbers (A000041) that are semiprimes (A001358).
LINKS
FORMULA
A000041(a(n)) in A014612.
EXAMPLE
a(1) = 9 because P(9) = 30 = 2 * 3 * 5.
a(2) = 10 because P(10) = 42 = 2 * 3 * 7.
a(3) = 16 because P(16) = 231 = 3 * 7 * 11.
CROSSREFS
Sequence in context: A105742 A105834 A280846 * A106690 A173015 A045568
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Aug 09 2006
EXTENSIONS
112 and 113 inserted by R. J. Mathar, Dec 22 2010
STATUS
approved

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Last modified April 19 23:40 EDT 2024. Contains 371798 sequences. (Running on oeis4.)