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.

Previous Showing 11-15 of 15 results.

A022275 a(n) = n*(17*n + 1)/2.

Original entry on oeis.org

0, 9, 35, 78, 138, 215, 309, 420, 548, 693, 855, 1034, 1230, 1443, 1673, 1920, 2184, 2465, 2763, 3078, 3410, 3759, 4125, 4508, 4908, 5325, 5759, 6210, 6678, 7163, 7665, 8184, 8720, 9273, 9843, 10430, 11034, 11655, 12293, 12948, 13620, 14309, 15015
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. A022274.
Cf. similar sequences listed in A022289.

Programs

  • Magma
    [n*(17*n + 1)/2: n in [0..45]]; // Vincenzo Librandi, Mar 31 2015
    
  • Mathematica
    Table[n (17 n + 1)/2, {n, 0, 40}] (* or *) LinearRecurrence[{3, -3, 1}, {0, 9, 35}, 40] (* Harvey P. Dale, May 06 2013 *)
    CoefficientList[Series[x (9 + 8 x) / (1 - x)^3, {x, 0, 40}], x] (* Vincenzo Librandi, Mar 31 2015 *)
  • PARI
    a(n)=n*(17*n+1)/2 \\ Charles R Greathouse IV, Jun 17 2017

Formula

a(n) = 17*n + a(n-1) - 8 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
a(0)=0, a(1)=9, a(2)=35; for n>2, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - Harvey P. Dale, May 06 2013
G.f.: x*(9+8*x)/(1-x)^3. - Vincenzo Librandi, Mar 31 2015
a(n) = A022274(-n). - Bruno Berselli, Mar 31 2015
a(n) = A000217(9*n) - A000217(8*n). - Bruno Berselli, Oct 13 2016
E.g.f.: (x/2)*(17*x + 18)*exp(x). - G. C. Greubel, Aug 23 2017

Extensions

More terms from Vincenzo Librandi, Mar 31 2015

A022277 a(n) = n*(19*n + 1)/2.

Original entry on oeis.org

0, 10, 39, 87, 154, 240, 345, 469, 612, 774, 955, 1155, 1374, 1612, 1869, 2145, 2440, 2754, 3087, 3439, 3810, 4200, 4609, 5037, 5484, 5950, 6435, 6939, 7462, 8004, 8565, 9145, 9744, 10362, 10999, 11655, 12330, 13024, 13737, 14469, 15220, 15990, 16779, 17587, 18414
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. A022276.
Cf. similar sequences listed in A022289.

Programs

Formula

a(n) = 19*n + a(n-1) - 9 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
G.f.: x*(10 + 9*x)/(1 - x)^3. - Vincenzo Librandi, Mar 31 2015
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>2. - Vincenzo Librandi, Mar 31 2015
a(n) = A022276(-n). - Bruno Berselli, Apr 01 2015
a(n) = A000217(10*n) - A000217(9*n). - Bruno Berselli, Oct 13 2016
E.g.f.: (x/2)*(19*x + 20)*exp(x). - G. C. Greubel, Aug 23 2017

Extensions

More terms from Vincenzo Librandi, Mar 31 2015

A022285 a(n) = n*(27*n + 1)/2.

Original entry on oeis.org

0, 14, 55, 123, 218, 340, 489, 665, 868, 1098, 1355, 1639, 1950, 2288, 2653, 3045, 3464, 3910, 4383, 4883, 5410, 5964, 6545, 7153, 7788, 8450, 9139, 9855, 10598, 11368, 12165, 12989, 13840, 14718, 15623
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. similar sequences listed in A022289.

Programs

Formula

a(n) = a(n-1) + 27*n - 13 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
a(0)=0, a(1)=14, a(2)=55; for n>2, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). -Harvey P. Dale, Sep 20 2011
G.f.: x*(13*x + 14)/(1-x)^3. - Harvey P. Dale, Sep 20 2011
a(n) = 12/(n+2)!*Sum_{j=0..n} (-1)^(n-j)*binomial(n,j)*(j+n)^(n+2). - Vladimir Kruchinin, Jun 04 2013
a(n) = A000217(14*n) - A000217(13*n). - Bruno Berselli, Oct 13 2016
E.g.f.: (x/2)*(27*x + 28)*exp(x). - G. C. Greubel, Aug 23 2017

A022287 a(n) = n*(29*n + 1)/2.

Original entry on oeis.org

0, 15, 59, 132, 234, 365, 525, 714, 932, 1179, 1455, 1760, 2094, 2457, 2849, 3270, 3720, 4199, 4707, 5244, 5810, 6405, 7029, 7682, 8364, 9075, 9815, 10584, 11382, 12209, 13065, 13950, 14864, 15807, 16779
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. similar sequences listed in A022289.

Programs

Formula

a(n) = 29*n + a(n-1) - 14 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
G.f.: x*(15 + 14*x)/(1 - x)^3 . - R. J. Mathar, Aug 04 2016
a(n) = A000217(15*n) - A000217(14*n). - Bruno Berselli, Oct 13 2016
E.g.f.: (x/2)*(29*x + 30)*exp(x). - G. C. Greubel, Aug 24 2017

A022279 a(n) = n*(21*n + 1)/2.

Original entry on oeis.org

0, 11, 43, 96, 170, 265, 381, 518, 676, 855, 1055, 1276, 1518, 1781, 2065, 2370, 2696, 3043, 3411, 3800, 4210, 4641, 5093, 5566, 6060, 6575, 7111, 7668, 8246, 8845, 9465, 10106, 10768, 11451, 12155
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. similar sequences listed in A022289.

Programs

Formula

a(n) = 21*n + a(n-1) - 10 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
a(0)=0, a(1)=11, a(2)=43; for n>2, a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - Harvey P. Dale, May 06 2014
a(n) = A000217(11*n) - A000217(10*n). - Bruno Berselli, Oct 13 2016
From G. C. Greubel, Aug 23 2017: (Start)
G.f.: x*(10*x + 11)/(1-x)^3.
E.g.f.: (x/2)*(21*x + 22)*exp(x). (End)
Previous Showing 11-15 of 15 results.