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A115402
Difference between 3-almostprime(n) and 3-almostprime(n+3).
1
12, 15, 10, 10, 15, 16, 15, 8, 8, 18, 16, 16, 7, 9, 8, 8, 17, 22, 21, 10, 7, 11, 12, 11, 7, 10, 9, 13, 14, 22, 18, 15, 7, 16, 12, 16, 7, 7, 4, 4, 10, 12, 13, 8, 9, 19, 22, 27, 23, 19, 14, 8, 11, 8
OFFSET
1,1
LINKS
FORMULA
a(n) = A014612(n+3) - A014612(n).
EXAMPLE
a(1) = A014612(1+3) - A014612(1) = 20 - 8 = 12.
a(2) = A014612(2+3) - A014612(2) = 27 - 12 = 15.
a(3) = A014612(3+3) - A014612(3) = 28 - 18 = 10.
a(39) = A014612(39+3) - A014612(39) = 174 - 170 = 4.
MATHEMATICA
Last[#]-First[#]&/@Partition[Select[Range[300], PrimeOmega[#]==3&], 4, 1] (* Harvey P. Dale, Nov 09 2012 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Jan 22 2006
STATUS
approved