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A184976
a(n) = [e]+[2*e]+...+[n*e], where []=floor.
1
2, 7, 15, 25, 38, 54, 73, 94, 118, 145, 174, 206, 241, 279, 319, 362, 408, 456, 507, 561, 618, 677, 739, 804, 871, 941, 1014, 1090, 1168, 1249, 1333, 1419, 1508, 1600, 1695, 1792, 1892, 1995, 2101, 2209, 2320, 2434, 2550, 2669, 2791, 2916, 3043, 3173, 3306, 3441, 3579, 3720
OFFSET
1,1
COMMENTS
It is interesting to note that a(n)/n^2 converges to e/2 .
LINKS
FORMULA
Partial sums of A022843.
EXAMPLE
a(3) = 15 because [2.71828...] + [2*2.71828...] + [3*2.71828...] = 2 + 5 + 8 = 15.
MAPLE
with(numtheory):Digits:=100:s:=0:e:=exp(1):for n from 1 to 100 do: s:=s+floor(n*e):printf(`%d,
`, s):od:
MATHEMATICA
Accumulate[Table[Floor[E n], {n, 60}]] (* Harvey P. Dale, Jan 14 2012 *)
PROG
(PARI) for(n=1, 50, print1(sum(k=1, n, floor(exp(1)*k)), ", ")) \\ G. C. Greubel, Jun 02 2017
CROSSREFS
Cf. A001113 (e), A022843.
Sequence in context: A375748 A167543 A332495 * A194140 A029888 A194112
KEYWORD
nonn
AUTHOR
Michel Lagneau, Mar 27 2011
STATUS
approved