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.

Showing 1-3 of 3 results.

A302763 Number of minimal total dominating sets in the n-antiprism graph.

Original entry on oeis.org

0, 4, 12, 28, 80, 52, 203, 524, 903, 2184, 3960, 9628, 20735, 41619, 93392, 194732, 425901, 908791, 1923408, 4177488, 8887289, 19098160, 40895771, 87444572, 187934955, 401853599, 861531618, 1846051011, 3953574901, 8476042452, 18151661911, 38898045292
Offset: 1

Views

Author

Eric W. Weisstein, Apr 12 2018

Keywords

Comments

Sequence extrapolated to n=1 using recurrence. - Andrew Howroyd, Apr 15 2018

Crossrefs

Programs

  • Mathematica
    Table[RootSum[-1 + 2 # + #^2 - 3 #^3 + 13 #^4 + 7 #^5 - 7 #^6 + 17 #^7 + 7 #^8 - 2 #^9 + 4 #^10 - 23 #^11 - 37 #^12 - 8 #^13 + 11 #^14 + 11 #^15 + 23 #^16 + 12 #^17 - 8 #^18 - 5 #^19 - 4 #^20 - 2 #^21 + #^23 &, #^n &], {n, 30}]
    RootSum[-1 + 2 # + #^2 - 3 #^3 + 13 #^4 + 7 #^5 - 7 #^6 + 17 #^7 + 7 #^8 - 2 #^9 + 4 #^10 - 23 #^11 - 37 #^12 - 8 #^13 + 11 #^14 + 11 #^15 + 23 #^16 + 12 #^17 - 8 #^18 - 5 #^19 - 4 #^20 - 2 #^21 + #^23 &, #^Range[30] &]
    LinearRecurrence[{0, 2, 4, 5, 8, -12, -23, -11, -11, 8, 37, 23, -4, 2, -7, -17, 7, -7, -13, 3, -1, -2, 1}, {0, 4, 12, 28, 80, 52, 203, 524, 903, 2184, 3960, 9628, 20735, 41619, 93392, 194732, 425901, 908791, 1923408, 4177488, 8887289, 19098160, 40895771}, 40]

Formula

G.f.: x^2*(4 + 12*x + 20*x^2 + 40*x^3 - 72*x^4 - 161*x^5 - 88*x^6 - 99*x^7 + 80*x^8 + 407*x^9 + 276*x^10 - 52*x^11 + 28*x^12 - 105*x^13 - 272*x^14 + 119*x^15 - 126*x^16 - 247*x^17 + 60*x^18 - 21*x^19 - 44*x^20 + 23*x^21)/(1 - 2*x^2 - 4*x^3 - 5*x^4 - 8*x^5 + 12*x^6 + 23*x^7 + 11*x^8 + 11*x^9 - 8*x^10 - 37*x^11 - 23*x^12 + 4*x^13 - 2*x^14 + 7*x^15 + 17*x^16 - 7*x^17 + 7*x^18 + 13*x^19 - 3*x^20 + x^21 + 2*x^22 - x^23). - Andrew Howroyd, Apr 15 2018

Extensions

a(1)-a(2) and terms a(11) and beyond from Andrew Howroyd, Apr 15 2018

A290510 Number of irredundant sets in the n-antiprism graph.

Original entry on oeis.org

1, 5, 22, 37, 76, 194, 491, 1125, 2731, 6640, 15962, 38386, 92639, 223403, 538102, 1297061, 3126726, 7535759, 18162481, 43777272, 105514634, 254314406, 612962766, 1477397778, 3560896401, 8582652759, 20686361179, 49859334611, 120173522734, 289648431514
Offset: 1

Views

Author

Eric W. Weisstein, Aug 04 2017

Keywords

Comments

The n-antiprism graphs are well defined for n>=3. Sequence extendend to n=1 using recurrence. - Andrew Howroyd, Aug 05 2017

Crossrefs

Formula

Empirical: a(n) = a(n-1)+2*a(n-2)+5*a(n-3) -6*a(n-5)-10*a(n-6) +6*a(n-8)+10*a(n-9)-a(n-10) -2*a(n-11)-5*a(n-12)+a(n-15) for n>15. - Andrew Howroyd, Aug 05 2017
Empirical g.f.: x*(1 + 4*x + 15*x^2 - 30*x^4 - 60*x^5 + 48*x^7 + 90*x^8 - 10*x^9 - 22*x^10 - 60*x^11 + 15*x^14) / ((1 - x)*(1 + x + x^2)*(1 - x - 2*x^2 - 4*x^3 - x^4 + 4*x^5 + 6*x^6 - x^7 - 2*x^8 - 4*x^9 + x^12)). - Colin Barker, Aug 05 2017

Extensions

a(1)-a(2) and terms a(11) and beyond from Andrew Howroyd, Aug 05 2017

A304568 Number of minimum dominating sets in the n-antiprism graph.

Original entry on oeis.org

2, 4, 15, 12, 5, 40, 14, 140, 45, 5, 154, 24, 546, 98, 5, 384, 34, 1485, 171, 5, 770, 44, 3289, 264, 5, 1352, 54, 6370, 377, 5, 2170, 64, 11220, 510, 5, 3264, 74, 18411, 663, 5, 4674, 84, 28595, 836, 5, 6440, 94, 42504, 1029, 5, 8602, 104, 60950, 1242, 5
Offset: 1

Views

Author

Eric W. Weisstein, May 14 2018

Keywords

Comments

Sequence extrapolated to n=1 using formula. - Andrew Howroyd, May 20 2018

Crossrefs

Programs

  • Mathematica
    Table[Piecewise[{{5, Mod[n, 5] == 0}, {2 n (4 + n) (13 + 2 n)/75, Mod[n, 5] == 1}, {2 n, Mod[n, 5] == 2}, {n (7 + n) (9 + 2 n) (19 + 2 n)/750, Mod[n, 5] == 3}, {n (7 + 2 n)/5, Mod[n, 5] == 4}}], {n, 30}]
    LinearRecurrence[{0, 0, 0, 0, 5, 0, 0, 0, 0, -10, 0, 0, 0, 0, 10, 0, 0, 0, 0, -5, 0, 0, 0, 0, 1}, {2, 4, 15, 12, 5, 40, 14, 140, 45, 5, 154, 24, 546, 98, 5, 384, 34, 1485, 171, 5, 770, 44, 3289, 264, 5}, 30]
    CoefficientList[Series[(5 x^4)/(1 - x^5) + (2 x (2 + 3 x^5))/(-1 + x^5)^2 + (x^3 (-12 - 9 x^5 + x^10))/(-1 + x^5)^3 + (2 (1 + 16 x^5 + 3 x^10))/(-1 + x^5)^4 + (x^2 (-15 - 65 x^5 + 4 x^10 - 5 x^15 + x^20))/(-1 + x^5)^5, {x, 0, 30}], x]
  • PARI
    a(n)={[k->5, k->2*(5*k+1)*(k+1)*(2*k+3)/3, k->2*(5*k+2), k->(5*k+3)*(2*k+5)*(2*k+4)*(2*k+3)/12, k->(5*k+4)*(2*k+3)][n%5+1](n\5)} \\ Andrew Howroyd, May 20 2018
    
  • PARI
    Vec(x*(2 + 4*x + 15*x^2 + 12*x^3 + 5*x^4 + 30*x^5 - 6*x^6 + 65*x^7 - 15*x^8 - 20*x^9 - 26*x^10 - 6*x^11 - 4*x^12 - 7*x^13 + 30*x^14 - 6*x^15 + 14*x^16 + 5*x^17 + 11*x^18 - 20*x^19 - 6*x^21 - x^22 - x^23 + 5*x^24) / ((1 - x)^5*(1 + x + x^2 + x^3 + x^4)^5) + O(x^40)) \\ Colin Barker, May 22 2018

Formula

From Andrew Howroyd, May 20 2018: (Start)
a(n) = 5*a(n-5) - 10*a(n-10) + 10*a(n-15) - 5*a(n-20) + a(n-25) for n > 25.
a(5*k) = 5, a(5*k+1) = 2*(5*k+1)*(k+1)*(2*k+3)/3, a(5*k+2) = 2*(5*k+2), a(5*k+3) = (5*k+3)*(2*k+5)*(2*k+4)*(2*k+3)/12, a(5*k+4)=(5*k+4)*(2*k+3). (End)
G.f.: x*(2 + 4*x + 15*x^2 + 12*x^3 + 5*x^4 + 30*x^5 - 6*x^6 + 65*x^7 - 15*x^8 - 20*x^9 - 26*x^10 - 6*x^11 - 4*x^12 - 7*x^13 + 30*x^14 - 6*x^15 + 14*x^16 + 5*x^17 + 11*x^18 - 20*x^19 - 6*x^21 - x^22 - x^23 + 5*x^24) / ((1 - x)^5*(1 + x + x^2 + x^3 + x^4)^5). - Colin Barker, May 22 2018

Extensions

a(1)-a(2) and terms a(21) and beyond from Andrew Howroyd, May 20 2018
Showing 1-3 of 3 results.