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A206224
Floor(n^2/4) appears 1+floor(n/2) times.
0
0, 0, 1, 1, 2, 2, 4, 4, 4, 6, 6, 6, 9, 9, 9, 9, 12, 12, 12, 12, 16, 16, 16, 16, 16, 20, 20, 20, 20, 20, 25, 25, 25, 25, 25, 25, 30, 30, 30, 30, 30, 30, 36, 36, 36, 36, 36, 36, 36, 42, 42, 42, 42, 42, 42, 42, 49, 49, 49, 49, 49, 49, 49, 49, 56, 56, 56, 56, 56
OFFSET
0,5
FORMULA
a(n) = floor((1/4)*(floor(sqrt(4*n+1))-1)^2)
= A002620(A000267(n)-1)
MAPLE
seq(floor((1/4)*(floor(sqrt(4*k+1))-1)^2), k=0..50)
MATHEMATICA
Flatten[Table[Table[Floor[n^2/4], {1 + Floor[n/2]}], {n, 0, 20}]] (* T. D. Noe, Feb 07 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Mircea Merca, Feb 05 2012
STATUS
approved