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A214206
a(n) = largest m such that m*(m+1)/2 <= 14*n.
5
0, 4, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 17, 18, 19, 20, 20, 21, 21, 22, 23, 23, 24, 24, 25, 25, 26, 27, 27, 28, 28, 28, 29, 29, 30, 30, 31, 31, 32, 32, 32, 33, 33, 34, 34, 35, 35, 35, 36, 36, 36, 37, 37, 38, 38, 38, 39, 39, 39, 40, 40, 40, 41, 41, 41, 42, 42, 42, 43, 43, 43, 44, 44, 44, 45, 45, 45, 45, 46, 46, 46, 47, 47, 47, 48, 48, 48, 48, 49, 49, 49, 49, 50
OFFSET
0,2
COMMENTS
Created in an attempt to simplify the definition of certain sequences currently under review by the editors.
LINKS
FORMULA
a(n) = A003056(14*n). - R. J. Mathar, Jul 09 2012
EXAMPLE
4*5/2 <= 14 but 5*6/2 > 14, so a(1)=4.
MATHEMATICA
Array[Floor[(Sqrt[1+112#]-1)/2]&, 100, 0] (* Harvey P. Dale, Dec 22 2012 *)
CROSSREFS
Sequence in context: A076680 A235623 A001074 * A026316 A283767 A174142
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 08 2012
STATUS
approved