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A182281
a(n) = floor(a(n-1)/3)+a(n-2) with a(0)=2, a(1)=3.
4
2, 3, 3, 4, 4, 5, 5, 6, 7, 8, 9, 11, 12, 15, 17, 20, 23, 27, 32, 37, 44, 51, 61, 71, 84, 99, 117, 138, 163, 192, 227, 267, 316, 372, 440, 518, 612, 722, 852, 1006, 1187, 1401, 1654, 1952, 2304, 2720, 3210, 3790, 4473, 5281, 6233, 7358, 8685, 10253, 12102
OFFSET
0,1
COMMENTS
a(n)/a(n-1) tends to (1+sqrt(37))/6 = 1.180460421716369948...
MATHEMATICA
RecurrenceTable[{a[0] == 2, a[1] == 3, a[n] == Floor[a[n - 1]/3] + a[n - 2]}, a, {n, 54}]
Transpose[NestList[{#[[2]], Floor[#[[2]]/3]+#[[1]]}&, {2, 3}, 60]][[1]] (* Harvey P. Dale, Nov 26 2015 *)
PROG
(Magma) [n le 2 select n+1 else Floor(Self(n-1)/3)+Self(n-2): n in [1..55]];
(Haskell)
a182281 n = a182281_list !! n
a182281_list = 2 : 3 : zipWith (+)
a182281_list (map (flip div 3) $ tail a182281_list)
-- Reinhard Zumkeller, Apr 30 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Bruno Berselli, Apr 21 2012
STATUS
approved