cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A022312 a(n) = a(n-1) + a(n-2) + 1 for n>1, a(0)=0, a(1)=7.

Original entry on oeis.org

0, 7, 8, 16, 25, 42, 68, 111, 180, 292, 473, 766, 1240, 2007, 3248, 5256, 8505, 13762, 22268, 36031, 58300, 94332, 152633, 246966, 399600, 646567, 1046168, 1692736, 2738905, 4431642, 7170548, 11602191, 18772740, 30374932, 49147673, 79522606, 128670280
Offset: 0

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Author

Keywords

Crossrefs

Cf. A000045.

Programs

Formula

Equals A022098(n) - 1.
G.f.: x*(7-6*x)/( (1-x)*(1-x-x^2) ). - R. J. Mathar, Apr 07 2011
a(n) = F(n+2) + 6*F(n) - 1, where F = A000045. - G. C. Greubel, Aug 25 2017

A295678 a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 2, a(2) = 1, a(3) = 3.

Original entry on oeis.org

1, 2, 1, 3, 6, 9, 13, 22, 37, 59, 94, 153, 249, 402, 649, 1051, 1702, 2753, 4453, 7206, 11661, 18867, 30526, 49393, 79921, 129314, 209233, 338547, 547782, 886329, 1434109, 2320438, 3754549, 6074987, 9829534, 15904521, 25734057, 41638578, 67372633, 109011211
Offset: 0

Views

Author

Clark Kimberling, Nov 27 2017

Keywords

Comments

Lim_{n->inf} a(n)/a(n-1) = (1 + sqrt(5))/2 = golden ratio (A001622), so that a( ) has the growth rate of the Fibonacci numbers (A000045).

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{1, 0, 1, 1}, {1, 2, 1, 3}, 100]

Formula

a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 2, a(2) = 1, a(3) = 3.
G.f.: (-1 - x + x^2 - x^3)/( (x^2+x-1)*(1+x^2)).
5*a(n) = A022098(n)+2*( A000034(n+1)*(-1)^floor(n/2)). - R. J. Mathar, Apr 26 2022

A217762 Square array T, read by antidiagonals: T(n,k) = F(n) + 2*F(k) where F(n) is the n-th Fibonacci number.

Original entry on oeis.org

0, 2, 1, 2, 3, 1, 4, 3, 3, 2, 6, 5, 3, 4, 3, 10, 7, 5, 4, 5, 5, 16, 11, 7, 6, 5, 7, 8, 26, 17, 11, 8, 7, 7, 10, 13, 42, 27, 17, 12, 9, 9, 10, 15, 21, 68, 43, 27, 18, 13, 11, 12, 15, 23, 34, 110, 69, 43, 28, 19, 15, 14, 17, 23, 36, 55, 178, 111, 69, 44, 29, 21
Offset: 0

Views

Author

Philippe Deléham, Apr 07 2013

Keywords

Examples

			Square array begins:
...0....2....2....4....6...10...16...26...42...
...1....3....3....5....7...11...17...27...43...
...1....3....3....5....7...11...17...27...43...
...2....4....4....6....8...12...18...28...44...
...3....5....5....7....9...13...19...29...45...
...5....7....7....9...11...15...21...31...47...
...8...10...10...12...14...18...24...34...50...
..13...15...15...17...19...23...29...39...55...
..21...23...23...25...27...31...37...47...63...
..34...36...36...38...40...44...50...60...76...
..55...57...57...59...61...65...71...81...97...
..89...91...91...93...95...99..105..115..131...
.144..146..146..148..150..154..160..170..186...
...
		

Crossrefs

Formula

T(n,0) = A000045(n).
T(1,k) = A001588(k).
T(n,1) = T(n,2) = A157725(n).
T(n,3) = A157727(n).
T(n,n)= A022086(n) = 3*A000045(n).
T(n+1,n) = A000032(n+1) = A000204(n+1).
T(n+2,n) = A000285(n).
T(n+3,n) = A013655(n+1) = A001060(n+1).
T(n+4,n) = A021120(n).
T(n+5,n) = A022088(n+2) = 5*A000045(n+2).
T(n+6,n) = A022097(n+2).
T(n+7,n) = A022122(n+2).
T(n+8,n) = 3*A013655(n+2).
T(n+9,n) = A097657(n+2).
T(n+10,n) = A022118(n+4).
T(n,n+1) = A000045(n+3).
T(n,n+2) = A013655(n+1) = A001060(n+1).
T(n,n+3) = A000032(n+3).
T(n,n+4) = A022095(n+2).
T(n,n+5) = A022120(n+2).
T(n,n+6) = A022136(n+2).
T(n,n+7) = A022098(n+4).
T(n,n+8) = A022380(n+4).
T(n,n+9) = A206419(n+6).
Sum(T(n-k,k), 0<=k<=n) = 3*A000071(n+2).
Previous Showing 11-13 of 13 results.