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A328943
a(n) = 2 + (n mod 4).
2
2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3, 4, 5, 2, 3
OFFSET
0,1
COMMENTS
Terms of the simple continued fraction of (36+sqrt(1806))/34.
2345/9999=0.234523452345...
Partial sums are given by A130482(n) + 2*n + 2.
Example of a sequence where the largest of any four consecutive terms equals the sum of the two smallest.
LINKS
David Nacin, Van der Laan Sequences and a Conjecture on Padovan Numbers, J. Int. Seq., Vol. 26 (2023), Article 23.1.2.
FORMULA
a(n) = 2 + (n mod 4).
G.f.: (5x^3 + 4x^2 + 3x + 2)/(1 - x^4).
a(n) = A010873(n) + 2 = A010883(n) + 1.
a(n) = 14 - a(n-1) - a(n-2) - a(n-3) for n > 2.
MATHEMATICA
PadRight[{}, 120, {2, 3, 4, 5}]
PROG
(Python)
def a(n):
...return n%4+2
CROSSREFS
KEYWORD
nonn
AUTHOR
David Nacin, Oct 31 2019
STATUS
approved