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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A100177 Structured meta-prism numbers, the n-th number from a structured n-gonal prism number sequence.

Original entry on oeis.org

1, 4, 18, 64, 175, 396, 784, 1408, 2349, 3700, 5566, 8064, 11323, 15484, 20700, 27136, 34969, 44388, 55594, 68800, 84231, 102124, 122728, 146304, 173125, 203476, 237654, 275968, 318739, 366300, 418996, 477184, 541233, 611524, 688450, 772416, 863839, 963148, 1070784, 1187200, 1312861, 1448244
Offset: 1

Views

Author

James A. Record (james.record(AT)gmail.com), Nov 07 2004

Keywords

Examples

			There are no 1- or 2-gonal prisms, so 1 and (2n) are used as the first and second terms since all the sequences begin as such.
		

Crossrefs

Cf. A002411, A000578, A050509, A006597, A100176, A100177 - structured prisms; A006484 for other meta structured numbers; and A100145 for more on structured numbers.

Programs

  • Magma
    [(1/6)*(3*n^4-9*n^3+12*n^2): n in [1..50] ]; // Vincenzo Librandi, Aug 02 2011
  • Mathematica
    Table[(3n^4-9n^3+12n^2)/6,{n,50}] (* or *) LinearRecurrence[{5,-10,10,-5,1},{1,4,18,64,175},50] (* Harvey P. Dale, Nov 07 2017 *)
  • PARI
    a(n)=(1/6)*(3*n^4-9*n^3+12*n^2);
    

Formula

a(n) = (1/6)*(3*n^4 - 9*n^3 + 12*n^2).
G.f.: x*(1 - x + 8*x^2 + 4*x^3)/(1-x)^5. - Colin Barker, Jun 08 2012
a(n) = A060354(n) * n = A000124(n-2) * n^2. - Bruce J. Nicholson, Jul 11 2018

A100185 Structured meta-anti-prism numbers, the n-th number from a structured n-gonal anti-prism number sequence.

Original entry on oeis.org

1, 4, 19, 68, 185, 416, 819, 1464, 2433, 3820, 5731, 8284, 11609, 15848, 21155, 27696, 35649, 45204, 56563, 69940, 85561, 103664, 124499, 148328, 175425, 206076, 240579, 279244, 322393, 370360, 423491, 482144
Offset: 1

Views

Author

James A. Record (james.record(AT)gmail.com)

Keywords

Examples

			There are no 1- or 2-gonal anti-prisms, so 1 and (2n) are used as the first and second terms since all the sequences begin as such.
		

Crossrefs

Cf. A005900, A000447, A096000, A100178, A100157, A100185 - structured anti-prisms; A006484 for other structured meta numbers; and A100145 for more on structured numbers.

Programs

  • Magma
    [(1/6)*(3*n^4-8*n^3+9*n^2+2*n): n in [1..40]]; // Vincenzo Librandi, Aug 03 2011

Formula

a(n) = (1/6)*(3*n^4 - 8*n^3 + 9*n^2 + 2*n).
G.f.: x*(1 - x + 9*x^2 + 3*x^3)/(1-x)^5. [Colin Barker, Jun 08 2012]

A051673 Cubic star numbers: a(n) = n^3 + 4*Sum_{i=0..n-1} i^2.

Original entry on oeis.org

0, 1, 12, 47, 120, 245, 436, 707, 1072, 1545, 2140, 2871, 3752, 4797, 6020, 7435, 9056, 10897, 12972, 15295, 17880, 20741, 23892, 27347, 31120, 35225, 39676, 44487, 49672, 55245, 61220, 67611, 74432, 81697, 89420, 97615, 106296, 115477, 125172
Offset: 0

Views

Author

Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de)

Keywords

Comments

Also as a(n) = (1/6)*(14*n^3 - 12*n^2 + 4*n), n>0: structured cubeoctahedral numbers (vertex structure 7); and structured pentagonal anti-diamond numbers (vertex structure 7) (cf. A004466 = alternate vertex) (cf. A100188 = structured anti-diamonds). Cf. A100145 for more on structured polyhedral numbers. - James A. Record (james.record(AT)gmail.com), Nov 07 2004
Starting with offset 1 = binomial transform of [1, 11, 24, 14, 0, 0, 0, ...]. - Gary W. Adamson, Aug 05 2009
This is prime for a(3) = 47. The subsequence of semiprimes begins: 707, 7435, 10897, 20741, 115477, 341797, 825091, 897097, no more through a(100). - Jonathan Vos Post, May 27 2010

Examples

			a(51) = 51*(51*(7*51-6)+2)/3 = 304351 = 17 * 17903 is semiprime. - _Jonathan Vos Post_, May 27 2010
		

References

  • T. A. Gulliver, Sequences from Arrays of Integers, Int. Math. Journal, Vol. 1, No. 4, pp. 323-332, 2002.

Crossrefs

Programs

Formula

a(n) = n*(n*(7*n-6) + 2)/3.
G.f.: x*(1+8*x+5*x^2)/(1-x)^4. - Bruno Berselli, May 12 2011
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4); a(0)=0, a(1)=1, a(2)=12, a(3)=47. - Harvey P. Dale, Jul 22 2011
From Reinhard Zumkeller, Jul 25 2012: (Start)
a(n) = A214659(n) - A002378(n).
a(n) = Sum_{k=1..n} A214661(n, k), for n > 0 (row sums). (End)
E.g.f.: (x/3)*(3 + 15*x + 7*x^2)*exp(x). - G. C. Greubel, Mar 10 2024

Extensions

Corrected by T. D. Noe, Nov 01 2006, Nov 08 2006

A096000 Cupolar numbers: a(n) = (n+1)*(5*n^2 + 7*n + 3)/3.

Original entry on oeis.org

1, 10, 37, 92, 185, 326, 525, 792, 1137, 1570, 2101, 2740, 3497, 4382, 5405, 6576, 7905, 9402, 11077, 12940, 15001, 17270, 19757, 22472, 25425, 28626, 32085, 35812, 39817, 44110, 48701, 53600, 58817, 64362, 70245, 76476, 83065, 90022, 97357, 105080, 113201, 121730
Offset: 0

Views

Author

N. J. A. Sloane, in memory of Harold Scott MacDonald Coxeter [Feb 09 1907 - Mar 31 2003], May 08 2004

Keywords

Comments

Number of equal balls that will fill a triangular cupola, formed by splitting a cuboctahedron along one of its four "equilateral" hexagons.
Also as a(n) = (1/6)*(10*n^3 - 6*n^2 + 10*n), n>0: structured pentagonal anti-prism numbers (Cf. A100185 = structured anti-prisms); and structured tetragonal anti-diamond numbers (vertex structure 7) (Cf. A000447 = alternate vertex; A100188 = structured anti-diamonds). Cf. A100145 for more on structured numbers. - James A. Record (james.record(AT)gmail.com), Nov 07 2004

References

  • H. S. M. Coxeter, Polyhedral numbers, pp. 25-35 of R. S. Cohen, J. J. Stachel and M. W. Wartofsky, eds., For Dirk Struik: Scientific, historical and political essays in honor of Dirk J. Struik, Reidel, Dordrecht, 1974.

Crossrefs

Programs

Formula

a(n) = (1/2)*(Q(n) + 3*n^2 + 3*n + 1), where Q(n) are the cuboctahedral numbers, A005902.
G.f.: (1+6*x+3*x^2)/(1-x)^4. - Paul Barry, Oct 28 2006
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4), n>3. - Wesley Ivan Hurt, May 23 2015
E.g.f.: exp(x)*(3 + 27*x + 27*x^2 + 5*x^3)/3. - Elmo R. Oliveira, Aug 11 2025

A100147 Structured icosidodecahedral numbers.

Original entry on oeis.org

1, 30, 135, 364, 765, 1386, 2275, 3480, 5049, 7030, 9471, 12420, 15925, 20034, 24795, 30256, 36465, 43470, 51319, 60060, 69741, 80410, 92115, 104904, 118825, 133926, 150255, 167860, 186789, 207090, 228811, 252000, 276705, 302974, 330855, 360396, 391645, 424650
Offset: 1

Views

Author

James A. Record (james.record(AT)gmail.com), Nov 07 2004

Keywords

Comments

Equals row sums of triangle A143254 & binomial transform of [1, 29, 76, 48, 0, 0, 0, ...]. - Gary W. Adamson, Aug 02 2008
Apart from offset, same as A079588.

Crossrefs

Cf. A100146, A100148 for adjacent structured Archimedean solids; and A100145 for more on structured polyhedral numbers.
Cf. also A079588.

Programs

Formula

a(n) = (1/6)*(48*n^3 - 60*n^2 + 18*n).
a(n) = A079588(n-1) = n*(2*n-1)*(4*n-3). - R. J. Mathar, Sep 02 2008
From Jaume Oliver Lafont, Sep 08 2009: (Start)
a(n) = (1+(n-1))*(1+2*(n-1))*(1+4*(n-1)).
G.f.: x*(1 + 26*x + 21*x^2)/(1-x)^4. (End)
E.g.f.: x*(1 + 14*x + 8*x^2)*exp(x). - G. C. Greubel, Oct 18 2018
From Amiram Eldar, Sep 20 2022: (Start)
Sum_{n>=1} 1/a(n) = Pi/3.
Sum_{n>=1} (-1)^(n+1)/a(n) = 2*sqrt(2)*log(sqrt(2)+1)/3 + log(2)/3 - (3 - 2*sqrt(2))*Pi/6. (End)

A100175 Structured triakis tetrahedral numbers (vertex structure 4).

Original entry on oeis.org

1, 8, 30, 76, 155, 276, 448, 680, 981, 1360, 1826, 2388, 3055, 3836, 4740, 5776, 6953, 8280, 9766, 11420, 13251, 15268, 17480, 19896, 22525, 25376, 28458, 31780, 35351, 39180, 43276, 47648, 52305, 57256, 62510, 68076, 73963, 80180, 86736, 93640, 100901, 108528
Offset: 1

Views

Author

James A. Record (james.record(AT)gmail.com), Nov 07 2004

Keywords

Comments

Equals binomial transform of [1, 7, 15, 9, 0, 0, 0, ...] where (1, 7, 15, 9) = row 3 of triangle A038763. - Gary W. Adamson, Jul 19 2008
Equals convolution square of 1, 4, 7, 10, 13, 16, 19, ..., A016777. - Gary W. Adamson, Jul 28 2009

Crossrefs

Cf. A000578 (alternate vertex), A100145 for more on structured numbers.
Cf. A038763.

Programs

  • Magma
    [(3*n^3-3*n^2+2*n)/2: n in [1..50] ]; // Vincenzo Librandi, Aug 02 2011
  • Mathematica
    CoefficientList[Series[x (2x+1)^2/((x-1)^4),{x,0,50}],x] (* or *) LinearRecurrence[{4,-6,4,-1},{0,1,8,30},50] (* Harvey P. Dale, Mar 18 2023 *)

Formula

a(n) = (3*n^3 - 3*n^2 + 2*n)/2.
G.f.: x*(2*x+1)^2 / ( (x-1)^4 ).

A006597 a(n) = n^2*(5*n-3)/2.

Original entry on oeis.org

0, 1, 14, 54, 136, 275, 486, 784, 1184, 1701, 2350, 3146, 4104, 5239, 6566, 8100, 9856, 11849, 14094, 16606, 19400, 22491, 25894, 29624, 33696, 38125, 42926, 48114, 53704, 59711, 66150, 73036, 80384, 88209, 96526, 105350, 114696, 124579, 135014, 146016, 157600
Offset: 0

Views

Author

Keywords

Comments

Structured heptagonal prism numbers. - James A. Record (james.record(AT)gmail.com), Nov 07 2004
Apart from 0, partial sums of A220083. - Bruno Berselli, Dec 11 2012

References

  • W. A. Whitworth, DCC Exercises in Choice and Chance, Stechert, NY, 1945, p. 29.

Crossrefs

Cf. A100177 - structured prisms; A100145 for more on structured numbers.
Cf. similar sequences, with the formula (k*n - k + 2)*n^2/2, listed in A262000.

Programs

Formula

a(n) = (1/6)*(15*n^3 - 9*n^2). - James A. Record (james.record(AT)gmail.com), Nov 07 2004
G.f.: x*(1+10*x+4*x^2)/(1-x)^4. - Colin Barker, Jun 08 2012
a(n) = Sum_{i=0..n-1} n*(5*i+1) for n>0. - Bruno Berselli, Sep 08 2015
Sum_{n>=1} 1/a(n) = 1.1080093773051638036... = (sqrt(5*(5 - 2*sqrt(5)))*Pi - Pi^2 - 5*sqrt(5)*arccoth(sqrt(5)) + (25*log(5))/2)/9. - Vaclav Kotesovec, Oct 04 2016
From Elmo R. Oliveira, Aug 06 2025: (Start)
E.g.f.: exp(x)*x*(2 + 12*x + 5*x^2)/2.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4).
a(n) = A006592(n)/4. (End)

Extensions

Name corrected by Arkadiusz Wesolowski, Jul 20 2011

A050509 House numbers (version 2): a(n) = (n+1)^3 + (n+1)*Sum_{i=0..n} i.

Original entry on oeis.org

1, 10, 36, 88, 175, 306, 490, 736, 1053, 1450, 1936, 2520, 3211, 4018, 4950, 6016, 7225, 8586, 10108, 11800, 13671, 15730, 17986, 20448, 23125, 26026, 29160, 32536, 36163, 40050, 44206, 48640, 53361, 58378, 63700, 69336, 75295, 81586, 88218, 95200, 102541
Offset: 0

Views

Author

Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Dec 28 1999

Keywords

Comments

Also as a(n) = (1/6)*(9*n^3 - 3*n^2), n>0: structured pentagonal prism numbers (Cf. A100177 - structured prisms; A100145 for more on structured numbers). - James A. Record (james.record(AT)gmail.com), Nov 07 2004
Number of inequivalent tetrahedral edge colorings using at most n+1 colors so that no color appears only once. - David Nacin, Feb 22 2017

Examples

			        *     *
a(2) = * * + * * = 10.
       * *   * *
		

Crossrefs

Cf. similar sequences, with the formula (k*n - k + 2)*n^2/2, listed in A262000.

Programs

  • Magma
    [(3*n+2)*(n+1)^2/2: n in [0..40]]; // Vincenzo Librandi, Jul 19 2011
    
  • Mathematica
    Table[((1+n)^2*(2+3n))/2,{n,0,40}] (* or *) LinearRecurrence[{4,-6,4,-1},{1,10,36,88},40] (* Harvey P. Dale, Jun 26 2011 *)
  • PARI
    a(n)=(1/2)*(3*n+2)*(n+1)^2 \\ Charles R Greathouse IV, Oct 07 2015

Formula

a(n) = A000578(n+1) + (n+1)*A000217(n).
a(n) = (1/2)*(3*n+2)*(n+1)^2.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4); a(0)=1, a(1)=10, a(2)=36, a(3)=88. - Harvey P. Dale, Jun 26 2011
G.f.: (1+6*x+2*x^2)/(1-x)^4. - Colin Barker, Jun 08 2012
a(n) = Sum_{i=0..n} (n+1)*(3*i+1). - Bruno Berselli, Sep 08 2015
Sum_{n>=0} 1/a(n) = 9*log(3) - sqrt(3)*Pi - Pi^2/3 = 1.15624437161388... . - Vaclav Kotesovec, Oct 04 2016
E.g.f.: exp(x)*(2 + 18*x + 17*x^2 + 3*x^3)/2. - Elmo R. Oliveira, Aug 06 2025

A100165 Structured rhombic triacontahedral numbers (vertex structure 7).

Original entry on oeis.org

1, 32, 147, 400, 845, 1536, 2527, 3872, 5625, 7840, 10571, 13872, 17797, 22400, 27735, 33856, 40817, 48672, 57475, 67280, 78141, 90112, 103247, 117600, 133225, 150176, 168507, 188272, 209525, 232320, 256711, 282752
Offset: 1

Views

Author

James A. Record (james.record(AT)gmail.com), Nov 07 2004

Keywords

Comments

Also structured pentakis dodecahedral numbers (vertex structure 7) (cf. A100173 = alternate vertex).

Crossrefs

Cf. A100164 = alternate vertex; A100145 for more on structured numbers.
Cf. A260260 (comment). [Bruno Berselli, Jul 22 2015]

Programs

  • Magma
    [(1/6)*(54*n^3-72*n^2+24*n): n in [1..40]]; // Vincenzo Librandi, Jul 26 2011
  • Mathematica
    Table[(3(n-1)+1)^2(3(n-1)+3)/3,{n,40}] (* Harvey P. Dale, Jan 02 2020 *)

Formula

a(n) = (1/6)*(54*n^3 - 72*n^2 + 24*n) = n*(3*n-2)^2.
From Jaume Oliver Lafont, Sep 08 2009: (Start)
a(n) = (3*(n-1) + 1)^2*(3*(n-1) + 3)/3.
G.f.: x*(1 + 28*x + 25*x^2)/(1-x)^4. (End)

A100158 Structured disdyakis triacontahedral numbers (vertex structure 11).

Original entry on oeis.org

1, 62, 293, 804, 1705, 3106, 5117, 7848, 11409, 15910, 21461, 28172, 36153, 45514, 56365, 68816, 82977, 98958, 116869, 136820, 158921, 183282, 210013, 239224, 271025, 305526, 342837, 383068, 426329, 472730, 522381, 575392
Offset: 1

Views

Author

James A. Record (james.record(AT)gmail.com), Nov 07 2004

Keywords

Comments

Also structured deltoidal hexacontahedral numbers (vertex structure 11) (cf. A100166, A100159 = alternate vertices).

Crossrefs

Cf. A100159, A100160 = alternate vertices; A100145 for more on structured polyhedral numbers.

Programs

  • Magma
    [(1/6)*(110*n^3-150*n^2+46*n): n in [1..40]]; // Vincenzo Librandi, Jul 19 2011
    
  • Mathematica
    Table[(110*n^3 - 150*n^2 + 46*n)/6, {n,1,50}] (* or *) LinearRecurrence[{4,-6,4,-1}, {1, 62, 293, 804}, 50] (* G. C. Greubel, Oct 18 2018 *)
  • PARI
    vector(50, n, (110*n^3 - 150*n^2 + 46*n)/6) \\ G. C. Greubel, Oct 18 2018

Formula

a(n) = (1/6)*(110*n^3 - 150*n^2 + 46*n).
G.f.: x*(1 + 58*x + 51*x^2)/(1-x)^4. - Colin Barker, Apr 16 2012
E.g.f.: x*(3 + 90*x + 55*x^2)*exp(x)/3. - G. C. Greubel, Oct 18 2018
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