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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A022101 Fibonacci sequence beginning 1, 11.

Original entry on oeis.org

1, 11, 12, 23, 35, 58, 93, 151, 244, 395, 639, 1034, 1673, 2707, 4380, 7087, 11467, 18554, 30021, 48575, 78596, 127171, 205767, 332938, 538705, 871643, 1410348, 2281991, 3692339, 5974330, 9666669, 15640999, 25307668, 40948667, 66256335, 107205002, 173461337, 280666339
Offset: 0

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Author

Keywords

Comments

a(n-1) = Sum_{k=0..ceiling((n-1)/2)} P(11;n-1-k,k) with n >= 1, a(-1)=10. These are the SW-NE diagonals in P(11;n,k), the (11,1) Pascal triangle. Cf. A093645 for the (10,1) Pascal triangle. Observation by Paul Barry, Apr 29 2004. Proof via recursion relations and comparison of inputs.
In general, for b Fibonacci sequence beginning with 1, h, we have:
b(n) = (2^(-1-n)*((1 - sqrt(5))^n*(1 + sqrt(5) - 2*h) + (1 + sqrt(5))^n*(-1 + sqrt(5) + 2*h)))/sqrt(5). - Herbert Kociemba, Dec 18 2011
Pisano period lengths: 1, 3, 8, 6, 20, 24, 16, 12, 24, 60, 10, 24, 28, 48, 40, 24, 36, 24, 18, 60, ... (is this A001175?). - R. J. Mathar, Aug 10 2012

Crossrefs

a(n) = A109754(10, n+1) = A101220(10, 0, n+1).

Programs

  • Magma
    a0:=1; a1:=11; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013
    
  • Mathematica
    LinearRecurrence[{1,1},{1,11},40] (* Harvey P. Dale, Aug 16 2015 *)
  • PARI
    a(n) = 10*fibonacci(n)+fibonacci(n+1) \\ Charles R Greathouse IV, Jun 11 2015

Formula

a(n) = a(n-1) + a(n-2), n >= 2, a(0)=1, a(1)=11. a(-1)=10.
G.f.: (1+10*x)/(1-x-x^2).
a(n-1) = ((1+sqrt(5))^n - (1-sqrt(5))^n)/(2^n*sqrt(5)) + 5*((1+sqrt(5))^(n-1) - (1-sqrt(5))^(n-1))/(2^(n-2)*sqrt(5)). - Al Hakanson (hawkuu(AT)gmail.com), Jan 14 2009
a(n) = 10*A000045(n) + A000045(n+1). - R. J. Mathar, Apr 07 2011
a(n) = 12*A000045(n) - A000045(n-2). - Bruno Berselli, Feb 20 2017
a(n) = A000045(n+4) + A000032(n-4) for n > 0. - Bruno Berselli, Sep 27 2017

A051880 a(n) = binomial(n+4,4)*(2*n+1).

Original entry on oeis.org

1, 15, 75, 245, 630, 1386, 2730, 4950, 8415, 13585, 21021, 31395, 45500, 64260, 88740, 120156, 159885, 209475, 270655, 345345, 435666, 543950, 672750, 824850, 1003275, 1211301, 1452465, 1730575, 2049720, 2414280, 2828936, 3298680, 3828825, 4425015, 5093235
Offset: 0

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Author

Barry E. Williams, Dec 14 1999

Keywords

Comments

Old name was: Partial sums of A051799.

References

  • Albert H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.
  • Herbert John Ryser, Combinatorial Mathematics, "The Carus Mathematical Monographs", No. 14, John Wiley and Sons, 1963, pp. 1-16.

Crossrefs

Cf. A051799.
Cf. A093645 ((10, 1) Pascal, column m=5).
A diagonal of A280880.

Programs

  • Mathematica
    Nest[Accumulate[#]&,Table[n(n+1)(10n-7)/6,{n,0,50}],2] (* Harvey P. Dale, Nov 13 2013 *)

Formula

a(n) = C(n+4, 4)*(2n+1).
G.f.: (1+9*x)/(1-x)^6.
From Amiram Eldar, Sep 04 2025: (Start)
Sum_{n>=0} 1/a(n) = 128*log(2)/35 - 152/105.
Sum_{n>=0} (-1)^n/a(n) = 32*Pi/35 + 596/105 - 384*log(2)/35. (End)

Extensions

Name changed by Alois P. Heinz, Jan 09 2017

A022102 Fibonacci sequence beginning 1, 12.

Original entry on oeis.org

1, 12, 13, 25, 38, 63, 101, 164, 265, 429, 694, 1123, 1817, 2940, 4757, 7697, 12454, 20151, 32605, 52756, 85361, 138117, 223478, 361595, 585073, 946668, 1531741, 2478409, 4010150, 6488559, 10498709
Offset: 0

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Author

Keywords

Comments

a(n-1) = Sum_{k=0..ceiling((n-1)/2)} P(12;n-1-k,k) with n>=1, a(-1)=11. These are the SW-NE diagonals in P(12;n,k), the (12,1) Pascal triangle. Cf. A093645 for the (10,1) Pascal triangle. Observation by Paul Barry, Apr 29 2004. Proof via recursion relations and comparison of inputs.
In general, for b Fibonacci sequence beginning with 1, h, we have:
b(n) = (2^(-1-n)*((1 - sqrt(5))^n*(1 + sqrt(5) - 2*h) + (1 + sqrt(5))^n*(-1 + sqrt(5) + 2*h)))/sqrt(5). - Herbert Kociemba, Dec 18 2011
Pisano period lengths: 1, 3, 8, 6, 20, 24, 16, 12, 24, 60, 10, 24, 28, 48, 40, 24, 36, 24, 18, 60, ... (is this A001175?). - R. J. Mathar, Aug 10 2012

Crossrefs

Programs

  • Magma
    a0:=1; a1:=12; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013
    
  • Mathematica
    LinearRecurrence[{1,1},{1,12},40] (* Harvey P. Dale, Jan 23 2012 *)
  • PARI
    a(n) = if(n==0, 1, if(n==1, 12, a(n-1)+a(n-2))) \\ Felix Fröhlich, Jun 09 2022
    
  • PARI
    Vec((1+11*x)/(1-x-x^2) + O(x^20)) \\ Felix Fröhlich, Jun 09 2022

Formula

a(n) = a(n-1) + a(n-2), n >= 2, a(0)=1, a(1)=12. a(-1):=11.
G.f.: (1+11*x)/(1-x-x^2).
a(n) = A109754(11, n+1) = A101220(11, 0, n+1).
a(n) = ((1+sqrt(5))^n - (1-sqrt(5))^n)/(2^n*sqrt(5)) + (11/2)*((1+sqrt(5))^(n-1)-(1-sqrt(5))^(n-1))/(2^(n-2)*sqrt(5)). Offset 1. a(3)=13. - Al Hakanson (hawkuu(AT)gmail.com), Jan 14 2009
a(n) = 11*A000045(n) + A000045(n+1). - R. J. Mathar, Aug 10 2012
a(n) = 13*A000045(n) - A000045(n-2). - Bruno Berselli, Feb 20 2017
a(n) = F(n+5) + F(n-1) - F(n-5) for F(n) the Fibonacci number A000045(n). - Greg Dresden and Aamen Muharram, Jun 09 2022

A022110 Fibonacci sequence beginning 1, 20.

Original entry on oeis.org

1, 20, 21, 41, 62, 103, 165, 268, 433, 701, 1134, 1835, 2969, 4804, 7773, 12577, 20350, 32927, 53277, 86204, 139481, 225685, 365166, 590851, 956017, 1546868, 2502885, 4049753, 6552638, 10602391, 17155029, 27757420, 44912449, 72669869, 117582318, 190252187
Offset: 0

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Author

Keywords

Comments

a(n-1) = Sum(P(20;n-1-k,k),k=0..ceiling((n-1)/2)), n>=1, with a(-1) = 19. These are the SW-NE diagonals in P(20;n,k), the (20,1) Pascal triangle. Cf. A093645 for the (10,1) Pascal triangle. Observation by Paul Barry, Apr 29 2004. Proof via recursion relations and comparison of inputs.

Crossrefs

a(n) = A109754(19, n+1) = A101220(19, 0, n+1).

Programs

  • Magma
    a0:=1; a1:=20; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013
  • Mathematica
    a={};b=1;c=20;AppendTo[a,b];AppendTo[a,c];Do[b=b+c;AppendTo[a,b];c=b+c;AppendTo[a,c],{n,1,12,1}];a (* Vladimir Joseph Stephan Orlovsky, Jul 23 2008 *)
    LinearRecurrence[{1, 1}, {1, 20}, 35] (* Paolo Xausa, Feb 22 2024 *)

Formula

a(n) = a(n-1)+a(n-2), n >= 2, a(0) = 1, a(1) = 20.
G.f.: (1+19*x)/(1-x-x^2).

A051799 Partial sums of A007587.

Original entry on oeis.org

1, 14, 60, 170, 385, 756, 1344, 2220, 3465, 5170, 7436, 10374, 14105, 18760, 24480, 31416, 39729, 49590, 61180, 74690, 90321, 108284, 128800, 152100, 178425, 208026, 241164, 278110, 319145, 364560, 414656, 469744, 530145, 596190
Offset: 0

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Author

Barry E. Williams, Dec 11 1999

Keywords

Comments

4-dimensional pyramidal number, composed of consecutive 3-dimensional slices; each of which is a 3-dimensional 12-gonal (or dodecagonal) pyramidal number; which in turn is composed of consecutive 2-dimensional slices 12-gonal numbers. - Jonathan Vos Post, Mar 17 2006
Convolution of A000027 with A051624 (excluding 0). - Bruno Berselli, Dec 07 2012

References

  • Albert H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.
  • Herbert John Ryser, Combinatorial Mathematics, "The Carus Mathematical Monographs", No. 14, John Wiley and Sons, 1963, pp. 1-8.
  • Murray R. Spiegel, Calculus of Finite Differences and Difference Equations, "Schaum's Outline Series", McGraw-Hill, 1971, pp. 10-20, 79-94.

Crossrefs

Cf. A093645 ((10, 1) Pascal, column m=4).
Cf. A220212 for a list of sequences produced by the convolution of the natural numbers with the k-gonal numbers.

Programs

Formula

a(n) = C(n+3, 3)*(5*n+2)/2 = (n+1)*(n+2)*(n+3)*(5*n+2)/12.
G.f.: (1+9*x)/(1-x)^5.
From Amiram Eldar, Feb 11 2022: (Start)
Sum_{n>=0} 1/a(n) = (125*log(5) + 10*sqrt(5*(5-2*sqrt(5)))*Pi - 50*sqrt(5)*log(phi) - 84)/104, where phi is the golden ratio (A001622).
Sum_{n>=0} (-1)^n/a(n) = (50*sqrt(5)*log(phi) + 5*sqrt(50-10*sqrt(5))*Pi - 256*log(2) + 90)/52. (End)

A022104 Fibonacci sequence beginning 1, 14.

Original entry on oeis.org

1, 14, 15, 29, 44, 73, 117, 190, 307, 497, 804, 1301, 2105, 3406, 5511, 8917, 14428, 23345, 37773, 61118, 98891, 160009, 258900, 418909, 677809, 1096718, 1774527, 2871245, 4645772, 7517017, 12162789
Offset: 0

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Author

Keywords

Comments

a(n-1)=sum(P(14;n-1-k,k),k=0..ceiling((n-1)/2)), n>=1, with a(-1)=13. These are the SW-NE diagonals in P(14;n,k), the (14,1) Pascal triangle. Cf. A093645 for the (10,1) Pascal triangle. Observation by Paul Barry, Apr 29 2004. Proof via recursion relations and comparison of inputs.

Crossrefs

a(n) = A109754(13, n+1) = A101220(13, 0, n+1).

Programs

  • Magma
    a0:=1; a1:=14; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013
  • Mathematica
    a={};b=1;c=14;AppendTo[a,b];AppendTo[a,c];Do[b=b+c;AppendTo[a,b];c=b+c;AppendTo[a,c],{n,1,9,1}];a (* Vladimir Joseph Stephan Orlovsky, Jul 22 2008 *)
    LinearRecurrence[{1,1},{1,14},40] (* Harvey P. Dale, Jun 12 2017 *)

Formula

a(n)= a(n-1)+a(n-2), n>=2, a(0)=1, a(1)=14. a(-1):=13.
G.f.: (1+13*x)/(1-x-x^2).

A022106 Fibonacci sequence beginning 1, 16.

Original entry on oeis.org

1, 16, 17, 33, 50, 83, 133, 216, 349, 565, 914, 1479, 2393, 3872, 6265, 10137, 16402, 26539, 42941, 69480, 112421, 181901, 294322, 476223, 770545, 1246768, 2017313, 3264081, 5281394, 8545475, 13826869
Offset: 0

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Author

Keywords

Comments

a(n-1)=sum(P(16;n-1-k,k),k=0..ceiling((n-1)/2)), n>=1, with a(-1)=15. These are the SW-NE diagonals in P(16;n,k), the (16,1) Pascal triangle. Cf. A093645 for the (10,1) Pascal triangle. Observation by Paul Barry, Apr 29 2004. Proof via recursion relations and comparison of inputs.

Crossrefs

a(n) = A109754(15, n+1) = A101220(15, 0, n+1).

Programs

  • Magma
    a0:=1; a1:=16; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013
  • Mathematica
    a={};b=1;c=16;AppendTo[a,b];AppendTo[a,c];Do[b=b+c;AppendTo[a,b];c=b+c;AppendTo[a,c],{n,1,12,1}];a (* Vladimir Joseph Stephan Orlovsky, Jul 23 2008 *)
    LinearRecurrence[{1,1},{1,16},40] (* Harvey P. Dale, Jun 22 2016 *)

Formula

a(n)= a(n-1)+a(n-2), n>=2, a(0)=1, a(1)=16. a(-1):=15.
G.f.: (1+15*x)/(1-x-x^2).

A022109 Fibonacci sequence beginning 1, 19.

Original entry on oeis.org

1, 19, 20, 39, 59, 98, 157, 255, 412, 667, 1079, 1746, 2825, 4571, 7396, 11967, 19363, 31330, 50693, 82023, 132716, 214739, 347455, 562194, 909649, 1471843, 2381492, 3853335, 6234827, 10088162, 16322989, 26411151, 42734140, 69145291, 111879431, 181024722
Offset: 0

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Author

Keywords

Comments

a(n-1) = Sum(P(19;n-1-k,k),k=0..ceiling((n-1)/2)), n>=1, with a(-1)=18. These are the SW-NE diagonals in P(19;n,k), the (19,1) Pascal triangle. Cf. A093645 for the (10,1) Pascal triangle. Observation by Paul Barry, Apr 29 2004. Proof via recursion relations and comparison of inputs.

Crossrefs

a(n) = A109754(18, n+1) = A101220(18, 0, n+1).

Programs

  • Magma
    a0:=1; a1:=19; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013
  • Mathematica
    LinearRecurrence[{1, 1}, {1, 19}, 35] (* Paolo Xausa, Feb 22 2024 *)

Formula

a(n) = a(n-1)+a(n-2), n >= 2, a(0) = 1, a(1) = 19.
G.f.: (1+18*x)/(1-x-x^2).

A050406 Partial sums of A051880.

Original entry on oeis.org

1, 16, 91, 336, 966, 2352, 5082, 10032, 18447, 32032, 53053, 84448, 129948, 194208, 282948, 403104, 562989, 772464, 1043119, 1388464, 1824130, 2368080, 3040830, 3865680, 4868955, 6080256, 7532721, 9263296
Offset: 0

Views

Author

Barry E. Williams, Dec 21 1999

Keywords

References

  • A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.

Crossrefs

Cf. A051880.
Cf. A093645 ((10, 1) Pascal, column m=6).

Programs

  • GAP
    List([0..40], n-> Binomial(n+5,5)*(5*n+3)/3); # G. C. Greubel, Oct 30 2019
  • Magma
    [Binomial(n+5,5)*(5*n+3)/3: n in [0..40]]; // G. C. Greubel, Oct 30 2019
    
  • Maple
    seq(binomial(n+5,5)*(5*n+3)/3, n=0..40); # G. C. Greubel, Oct 30 2019
  • Mathematica
    Nest[Accumulate[#]&,Table[n(n+1)(10n-7)/6,{n,0,50}],3] (* Harvey P. Dale, Nov 13 2013 *)
  • PARI
    vector(41, n, binomial(n+4,5)*(5*n-2)/3) \\ G. C. Greubel, Oct 30 2019
    
  • Sage
    [binomial(n+5,5)*(5*n+3)/3 for n in (0..40)] # G. C. Greubel, Oct 30 2019
    

Formula

a(n) = C(n+5, 5)*(5*n + 3)/3.
G.f.: (1+9*x)/(1-x)^7.
E.g.f.: (360 +5400*x +10800*x^2 +6600*x^3 +1575*x^4 +153*x^5 +5*x^6) *exp(x)/360. - G. C. Greubel, Oct 30 2019

Extensions

Corrected by T. D. Noe, Nov 09 2006

A052254 Partial sums of A050406.

Original entry on oeis.org

1, 17, 108, 444, 1410, 3762, 8844, 18876, 37323, 69355, 122408, 206856, 336804, 531012, 813960, 1217064, 1780053, 2552517, 3595636, 4984100, 6808230, 9176310, 12217140, 16082820, 20951775
Offset: 0

Views

Author

Barry E. Williams, Feb 03 2000

Keywords

References

  • A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.
  • Murray R. Spiegel, Calculus of Finite Differences and Difference Equations, "Schaum's Outline Series", McGraw-Hill, 1971, pp. 10-20, 79-94.

Crossrefs

Cf. A050406.
Cf. A093645 ((10, 1) Pascal, column m=7).

Programs

  • GAP
    List([0..30], n-> (10*n+7)*Binomial(n+6, 6)/7 ); # G. C. Greubel, Jan 19 2020
  • Magma
    [(10*n+7)*Binomial(n+6, 6)/7: n in [0..30]]; // G. C. Greubel, Jan 19 2020
    
  • Maple
    seq( (10*n+7)*binomial(n+6, 6)/7, n=0..30); # G. C. Greubel, Jan 19 2020
  • Mathematica
    Table[10*Binomial[n+7,7] -9*Binomial[n+6,6], {n,0,30}] (* G. C. Greubel, Jan 19 2020 *)
    Rest[Nest[Accumulate[#]&,Table[n(n+1)(10n-7)/6,{n,0,50}],4]] (* Harvey P. Dale, Aug 03 2020 *)
  • PARI
    vector(31, n, (10*n-3)*binomial(n+5, 6)/7) \\ G. C. Greubel, Jan 19 2020
    
  • Sage
    [(10*n+7)*binomial(n+6, 6)/7 for n in (0..30)] # G. C. Greubel, Jan 19 2020
    

Formula

a(n) = (10*n + 7)*binomial(n+6, 6)/7.
G.f.: (1+9*x)/(1-x)^8.
From G. C. Greubel, Jan 19 2020: (Start)
a(n) = 10*binomial(n+7, 7) - 9*binomial(n+6, 6).
E.g.f.: (7! + 80640*x + 189000*x^2 + 142800*x^3 + 45150*x^4 + 6552*x^5 + 427*x^6 + 10*x^7)*exp(x)/7!. (End)
a(n) = 8*a(n-1)-28*a(n-2)+56*a(n-3)-70*a(n-4)+56*a(n-5)-28*a(n-6)+8*a(n-7)-a(n-8). - Wesley Ivan Hurt, Nov 28 2021
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