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A127838 a(1) = 1, a(2) = a(3) = a(4) = 0, a(n) = a(n-4)+a(n-3) for n>4. 0
1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 2, 1, 1, 3, 3, 2, 4, 6, 5, 6, 10, 11, 11, 16, 21, 22, 27, 37, 43, 49, 64, 80, 92, 113, 144, 172, 205, 257, 316, 377, 462, 573, 693, 839, 1035, 1266, 1532, 1874, 2301, 2798, 3406, 4175, 5099, 6204, 7581 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,12

COMMENTS

Part of the phi_k family of sequences defined by a(1)=1, a(2)= ...=a(k)=0, a(n) =a(n-k) +a(n-k+1) for n>k. phi_2 is a shift of the Fibonacci sequence and phi_3 is a shift of the Padovan sequence.

The sequence can be interpreted as the top-left element of the n-th power of 6 different 4X4 (0,1) matrices. - R. J. Mathar, Mar 19 2014

REFERENCES

G. Mantel, Resten van wederkeerige Reeksen, Nieuw Archief v. Wiskunde, 2nd series, I (1894), 172-184. [From N. J. A. Sloane, Dec 17 2010]

S. Suter, Binet-like formulas for recurrent sequences with characteristic equation x^k=x+1, preprint, 2007, apparently unpublished as of Mar 2014.

LINKS

Table of n, a(n) for n=1..56.

Index entries for linear recurrences with constant coefficients, signature (0,0,1,1).

FORMULA

Binet-like formula: a(n)=sum_{i=1...4} (r_i^n)/(3(r_i)^2+4(r_i)) where r_i is a root of x^4=x+1

a(n)=A017817(n-5) for n>=5. O.g.f.: x(x-1)(1+x+x^2)/(x^4+x^3-1). - R. J. Mathar, Mar 06 2008

MAPLE

P:=proc(n) local a, a0, a1, a2, a3, a4, i; a0:=1; a1:=0; a2:=0; a3:=0; print(a0); print(a1); print(a2); print(a3); for i from 1 by 1 to n do a:=a0+a1; a0:=a1; a1:=a2; a2:=a3; a3:=a; print(a); od; end: P(100); - Paolo P. Lava, Jun 28 2007

MATHEMATICA

LinearRecurrence[{0, 0, 1, 1}, {1, 0, 0, 0}, 60] (* Harvey P. Dale, Feb 15 2015 *)

CROSSREFS

Sequence in context: A247749 A247367 A305321 * A017817 A284834 A279677

Adjacent sequences:  A127835 A127836 A127837 * A127839 A127840 A127841

KEYWORD

nonn,easy

AUTHOR

Stephen Suter (sms5064(AT)psu.edu), Apr 02 2007

STATUS

approved

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Last modified October 20 07:17 EDT 2018. Contains 316378 sequences. (Running on oeis4.)