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A228848
a(n) = round(3*n^2/Pi^2).
0
0, 0, 1, 3, 5, 8, 11, 15, 19, 25, 30, 37, 44, 51, 60, 68, 78, 88, 98, 110, 122, 134, 147, 161, 175, 190, 205, 222, 238, 256, 274, 292, 311, 331, 351, 372, 394, 416, 439, 462, 486, 511, 536, 562, 588, 616, 643, 671, 700, 730, 760, 791, 822, 854, 886, 919, 953
OFFSET
0,4
COMMENTS
a(n) is the asymptotic limit of A005728(n) and of A015614(n).
REFERENCES
Albert H. Beiler, Recreations in the theory of numbers, New York, Dover, (2nd ed.) 1966. See Table 71 at p. 171.
FORMULA
a(n) = round(A033428(n)/Pi^2).
a(n) ~ A104141*n^2.
MATHEMATICA
Round[(3*Range[0, 60]^2)/Pi^2] (* Harvey P. Dale, Dec 18 2013 *)
PROG
(PARI) for(n=0, 56, print1(round(3*(n/Pi)^2), ", "))
(Sage) [round(3*n^2/pi^2) for n in range(0, 57)] # Stefano Spezia, Aug 06 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved