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A061887
n + largest square less than or equal to n; numbers in the range [2k^2,2k^2+2k] for some k.
2
0, 2, 3, 4, 8, 9, 10, 11, 12, 18, 19, 20, 21, 22, 23, 24, 32, 33, 34, 35, 36, 37, 38, 39, 40, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 128, 129
OFFSET
0,2
FORMULA
a(n) = n+[sqrt(n)]^2 = n+A048760(n) = 2n-A053186(n).
EXAMPLE
a(15)=15+9=24; a(16)=16+16=32; a(17)=17+16=33.
MATHEMATICA
Table[n+Floor[Sqrt[n]]^2, {n, 0, 70}] (* Harvey P. Dale, Aug 23 2012 *)
CROSSREFS
Sequence in context: A309314 A309326 A326701 * A005455 A047338 A069811
KEYWORD
nonn
AUTHOR
Henry Bottomley, May 12 2001
STATUS
approved