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A162731
a(n) is the n-th triprime (A014612) minus its central prime factor.
0
6, 10, 15, 18, 24, 26, 27, 39, 42, 42, 45, 50, 60, 63, 66, 65, 70, 74, 75, 90, 91, 96, 99, 100, 105, 111, 114, 114, 122, 120, 125, 135, 140, 146, 150, 147, 162, 160, 165, 168, 170, 171, 170, 175, 183, 186, 185, 190, 204, 210, 219, 225, 224, 234, 231, 231, 242, 238, 243, 250
OFFSET
1,1
FORMULA
a(n) = A014612(n) - A162361(n).
EXAMPLE
a(1) = 6 = 2*2*2 - 2;
a(2) = 10 = 2*2*3 - 2;
a(3) = 15 = 2*3*3 - 3;
a(4) = 18 = 2*2*5 - 2;
a(5) = 24 = 3*3*3 - 3.
CROSSREFS
Sequence in context: A315241 A166160 A315242 * A315243 A315244 A315245
KEYWORD
nonn,less
AUTHOR
EXTENSIONS
Definition reformulated, a(11), a(38) etc. corrected by R. J. Mathar, Jul 16 2009
STATUS
approved