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A086213
Tribonacci numbers that start with first three cubes.
1
1, 8, 27, 36, 71, 134, 241, 446, 821, 1508, 2775, 5104, 9387, 17266, 31757, 58410, 107433, 197600, 363443, 668476, 1229519, 2261438, 4159433, 7650390, 14071261, 25881084, 47602735, 87555080, 161038899, 296196714, 544790693, 1002026306
OFFSET
0,2
LINKS
Martin Burtscher, Igor Szczyrba, and RafaƂ Szczyrba, Analytic Representations of the n-anacci Constants and Generalizations Thereof, Journal of Integer Sequences, Vol. 18 (2015), Article 15.4.5.
FORMULA
a(n) = a(n-1) + a(n-2) + a(n-3).
G.f.: (1+7x+18x^2)/(1-x-x^2-x^3).
MAPLE
a[0] := 1: a[1] := 8: a[2] := 27: for n from 3 to 40 do a[n] := a[n-1]+a[n-2]+a[n-3] od: seq(a[n], n=0..40);
MATHEMATICA
LinearRecurrence[{1, 1, 1}, {1, 8, 27}, 32] (* Ray Chandler, Dec 08 2013 *)
CROSSREFS
Sequence in context: A352423 A371955 A066215 * A175050 A063142 A235994
KEYWORD
nonn,easy
AUTHOR
Jun Mizuki (suzuki32(AT)sanken.osaka-u.ac.jp), Aug 28 2003
EXTENSIONS
Edited by Emeric Deutsch, Mar 09 2004
STATUS
approved