This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A099464 Trisection of tribonacci numbers. 4
 0, 1, 7, 44, 274, 1705, 10609, 66012, 410744, 2555757, 15902591, 98950096, 615693474, 3831006429, 23837527729, 148323355432, 922906855808, 5742568741225, 35731770264967, 222332455004452, 1383410902447554, 8607945812375585, 53560898629395777, 333269972246340068 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Let A = [1,1,1; 2,4,3; 1,2,2]. a(n) is given by the (1,2) term in A^n. LINKS Index entries for linear recurrences with constant coefficients, signature (7,-5,1). FORMULA G.f.: x/(1-7*x+5*x^2-x^3). a(n) = 7a(n-1) -5a(n-2) +a(n-3). a(n) = A000073(3n). a(n) = Sum_{i>=n-1} A120987(i,n-1) for n>0. - Alois P. Heinz, Dec 11 2015 MAPLE a:= n-> (<<0|1|0>, <0|0|1>, <1|-5|7>>^n)[3, 1]: seq(a(n), n=0..30);  # Alois P. Heinz, Dec 11 2015 MATHEMATICA LinearRecurrence[{7, -5, 1}, {0, 1, 7}, 30] (* Harvey P. Dale, Jan 14 2016 *) CROSSREFS Cf. A009943, A120987. Sequence in context: A218992 A190974 A027279 * A254660 A093738 A091127 Adjacent sequences:  A099461 A099462 A099463 * A099465 A099466 A099467 KEYWORD easy,nonn AUTHOR Paul Barry, Oct 16 2004 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified November 18 09:21 EST 2017. Contains 294879 sequences.