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A145028 Tetranacci numbers: a(n)=a(n-1)+a(n-2)+a(n-3)+a(n-4), {1,2,3,4...}. 0
1, 2, 3, 4, 10, 19, 36, 69, 134, 258, 497, 958, 1847, 3560, 6862, 13227, 25496, 49145, 94730, 182598, 351969, 678442, 1307739, 2520748, 4858898, 9365827, 18053212, 34798685, 67076622, 129294346, 249222865, 480392518, 925986351, 1784896080 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..34.

Index entries for linear recurrences with constant coefficients, signature (1, 1, 1, 1).

FORMULA

G.f.: x*(1-x)*(1+2*x+2*x^2)/(1-x-x^2-x^3-x^4). [Colin Barker, Jan 11 2012]

MATHEMATICA

LinearRecurrence[{1, 1, 1, 1}, {1, 2, 3, 4}, 30]

CROSSREFS

Sequence in context: A135432 A108364 A346489 * A306107 A229545 A085932

Adjacent sequences:  A145025 A145026 A145027 * A145029 A145030 A145031

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Sep 30 2008

STATUS

approved

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Last modified September 18 13:54 EDT 2021. Contains 347527 sequences. (Running on oeis4.)