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 1-7 of 7 results.

A170801 a(n) = n^10*(n^9 + 1)/2.

Original entry on oeis.org

0, 1, 262656, 581160258, 137439477760, 9536748046875, 304679900238336, 5699447733924196, 72057594574798848, 675425860579888245, 5000000005000000000, 30579545237175985446, 159739999716270145536
Offset: 0

Views

Author

N. J. A. Sloane, Dec 11 2009

Keywords

Comments

Number of unoriented rows of length 19 using up to n colors. For a(0)=0, there are no rows using no colors. For a(1)=1, there is one row using that one color for all positions. For a(2)=262656, there are 2^19=524288 oriented arrangements of two colors. Of these, 2^10=1024 are achiral. That leaves (524288-1024)/2=261632 chiral pairs. Adding achiral and chiral, we get 262656. - Robert A. Russell, Nov 13 2018

Crossrefs

Row 19 of A277504.
Cf. A010807 (oriented), A008454 (achiral).
Sequences of the form n^10*(n^m + 1)/2: A170793 (m=1), A170794 (m=2), A170795 (m=3), A170796 (m=4), A170797 (m=5), A170798 (m=6), A170799 (m=7), A170800 (m=8), this sequence (m=9), A170802 (m=10).

Programs

  • GAP
    List([0..30], n -> n^10*(n^9+1)/2); # G. C. Greubel, Nov 15 2018
  • Magma
    [n^10*(n^9+1)/2: n in [0..20]]; // Vincenzo Librandi, Aug 27 2011
    
  • Maple
    seq(n^10*(n^9 +1)/2, n=0..20); # G. C. Greubel, Oct 11 2019
  • Mathematica
    Table[(n^19 + n^10)/2, {n,0,30}] (* Robert A. Russell, Nov 13 2018 *)
  • PARI
    vector(30, n, n--; n^10*(n^9+1)/2) \\ G. C. Greubel, Nov 15 2018
    
  • Sage
    [n^10*(n^9+1)/2 for n in range(30)] # G. C. Greubel, Nov 15 2018
    

Formula

From Robert A. Russell, Nov 13 2018: (Start)
a(n) = (A010807(n) + A008454(n)) / 2 = (n^19 + n^10) / 2.
G.f.: (Sum_{j=1..19} S2(19,j)*j!*x^j/(1-x)^(j+1) + Sum_{j=1..10} S2(10,j)*j!*x^j/(1-x)^(j+1)) / 2, where S2 is the Stirling subset number A008277.
G.f.: x*Sum_{k=0..18} A145882(19,k) * x^k / (1-x)^20.
E.g.f.: (Sum_{k=1..19} S2(19,k)*x^k + Sum_{k=1..10} S2(10,k)*x^k) * exp(x) / 2, where S2 is the Stirling subset number A008277.
For n>19, a(n) = Sum_{j=1..20} -binomial(j-21,j) * a(n-j). (End)

A170802 a(n) = n^10*(n^10 + 1)/2.

Original entry on oeis.org

0, 1, 524800, 1743421725, 549756338176, 47683720703125, 1828079250264576, 39896133290043625, 576460752840294400, 6078832731271856601, 50000000005000000000, 336374997479248716901, 1916879996254696243200
Offset: 0

Views

Author

N. J. A. Sloane, Dec 11 2009

Keywords

Comments

By definition, all terms are triangular numbers. - Harvey P. Dale, Aug 12 2012
Number of unoriented rows of length 20 using up to n colors. For a(0)=0, there are no rows using no colors. For a(1)=1, there is one row using that one color for all positions. For a(2)=524800, there are 2^20=1048576 oriented arrangements of two colors. Of these, 2^10=1024 are achiral. That leaves (1048576-1024)/2=523776 chiral pairs. Adding achiral and chiral, we get 524800. - Robert A. Russell, Nov 13 2018

Crossrefs

Row 20 of A277504.
Cf. A010808 (oriented), A008454 (achiral).
Sequences of the form n^10*(n^m + 1)/2: A170793 (m=1), A170794 (m=2), A170795 (m=3), A170896 (m=4), A170797 (m=5), A170798 (m=6), A170799 (m=7), A170800 (m=8), A170801 (m=9), this sequence (m=10).

Programs

  • GAP
    List([0..30], n -> n^10*(n^10+1)/2); # G. C. Greubel, Nov 15 2018
    
  • Magma
    [n^10*(n^10+1)/2: n in [0..20]]; // Vincenzo Librandi, Aug 27 2011
    
  • Maple
    seq(n^10*(n^10 +1)/2, n=0..20); # G. C. Greubel, Oct 11 2019
  • Mathematica
    n10[n_]:=Module[{c=n^10},(c(c+1))/2];Array[n10,15,0] (* Harvey P. Dale, Jul 17 2012 *)
  • PARI
    vector(30, n, n--; n^10*(n^10+1)/2) \\ G. C. Greubel, Nov 15 2018
    
  • Python
    for n in range(0,20): print(int(n**10*(n**10 + 1)/2), end=', ') # Stefano Spezia, Nov 15 2018
  • Sage
    [n^10*(n^10+1)/2 for n in range(30)] # G. C. Greubel, Nov 15 2018
    

Formula

From Robert A. Russell, Nov 13 2018: (Start)
a(n) = (A010808(n) + A008454(n)) / 2 = (n^20 + n^10) / 2.
G.f.: (Sum_{j=1..20} S2(20,j)*j!*x^j/(1-x)^(j+1) + Sum_{j=1..10} S2(10,j)*j!*x^j/(1-x)^(j+1)) / 2, where S2 is the Stirling subset number A008277.
G.f.: x*Sum_{k=0..19} A145882(20,k) * x^k / (1-x)^21.
E.g.f.: (Sum_{k=1..20} S2(20,k)*x^k + Sum_{k=1..10} S2(10,k)*x^k) * exp(x) / 2, where S2 is the Stirling subset number A008277.
For n>20, a(n) = Sum_{j=1..21} -binomial(j-22,j) * a(n-j). (End)

A283029 Number of inequivalent 5 X 5 matrices with entries in {1,2,3,..,n} when a matrix and its transpose are considered equivalent.

Original entry on oeis.org

0, 1, 16793600, 423651479175, 562950490292224, 149011627197265625, 14215144250057342976, 670534312205763205375, 18889465949070766899200, 358948993948871860432449, 5000000000500000000000000, 54173529719030485105622951, 476981083228048575587942400
Offset: 0

Views

Author

David Nacin, Feb 27 2017

Keywords

Comments

Cycle index of symmetric group S2 acting on the set of 25 entries is (s(2)^10*s(1)^5 + s(1)^25)/2.

Examples

			For n=2 we get a(2)=16793600 inequivalent 5x5 binary matrices up to the action of transposition.
		

Crossrefs

Cf. A282612,A282613,A282614. A283026, A283027, A283028, A283030, A283031, A283032, A283033. A170798 (4x4 version). A168555 (3x3 version). A019582 (2x2 version)

Programs

  • Mathematica
    Table[n^15 (n^2 + 1) (n^8 - n^6 + n^4 - n^2 + 1)/2, {n, 0, 12}]
  • PARI
    a(n) = n^15*(n^2+1)*(n^8-n^6+n^4-n^2+1)/2; \\ Indranil Ghosh, Feb 27 2017
    
  • Python
    def A283029(n): return n**15*(n**2+1)*(n**8-n**6+n**4-n**2+1)/2 # Indranil Ghosh, Feb 27 2017

Formula

a(n) = n^15*(n^2+1)*(n^8-n^6+n^4-n^2+1)/2.
From Chai Wah Wu, Dec 07 2018: (Start)
a(n) = 26*a(n-1) - 325*a(n-2) + 2600*a(n-3) - 14950*a(n-4) + 65780*a(n-5) - 230230*a(n-6) + 657800*a(n-7) - 1562275*a(n-8) + 3124550*a(n-9) - 5311735*a(n-10) + 7726160*a(n-11) - 9657700*a(n-12) + 10400600*a(n-13) - 9657700*a(n-14) + 7726160*a(n-15) - 5311735*a(n-16) + 3124550*a(n-17) - 1562275*a(n-18) + 657800*a(n-19) - 230230*a(n-20) + 65780*a(n-21) - 14950*a(n-22) + 2600*a(n-23) - 325*a(n-24) + 26*a(n-25) - a(n-26) for n > 25.
G.f.: x*(x^24 + 16793574*x^23 + 423214845900*x^22 + 551941009751074*x^21 + 134512557517054626*x^20 + 10522699609491808746*x^19 + 347912001753554722204*x^18 + 5696453728178627889150*x^17 + 50977946159336791604079*x^16 + 265857130683340877431996*x^15 + 842694350441988138095256*x^14 + 1667306282568523129263444*x^13 + 2089823554970188253479900*x^12 + 1667306282568523129263444*x^11 + 842694350441988138095256*x^10 + 265857130683340877431996*x^9 + 50977946159336791604079*x^8 + 5696453728178627889150*x^7 + 347912001753554722204*x^6 + 10522699609491808746*x^5 + 134512557517054626*x^4 + 551941009751074*x^3 + 423214845900*x^2 + 16793574*x + 1)/(x - 1)^26. (End)

A170797 a(n) = n^10*(n^5+1)/2.

Original entry on oeis.org

0, 1, 16896, 7203978, 537395200, 15263671875, 235122725376, 2373921992596, 17592722915328, 102947309439525, 500005000000000, 2088637053420126, 7703541745975296, 25593015436291303, 77784192406233600
Offset: 0

Views

Author

N. J. A. Sloane, Dec 11 2009

Keywords

Crossrefs

Sequences of the form n^10*(n^m + 1)/2: A170793 (m=1), A170794 (m=2), A170795 (m=3), A170796 (m=4), this sequence (m=5), A170798 (m=6), A170799 (m=7), A170800 (m=8), A170801 (m=9), A170802 (m=10).

Programs

Formula

G.f.: x*(15872*x^13 +6890977*x^12 +423932400*x^11 +7520863426*x^10 +51389080880*x^9 +155692452591*x^8 +223769408736*x^7 +155695145820*x^6 +51387918048*x^5 +7520366095*x^4 +424158512*x^3 +6933762*x^2 +16880*x +1) / (x-1)^16. - Colin Barker, Nov 01 2014
a(n) = 16*a(n-1) - 120*a(n-2) + 560*a(n-3) - 1820*a(n-4) + 4368*a(n-5) - 8008*a(n-6) + 11440*a(n-7) - 12870*a(n-8) + 11440*a(n-9) - 8008*a(n-10) + 4368*a(n-11) - 1820*a(n-12) + 560*a(n-13) - 120*a(n-14) + 16*a(n-15) - a(n-16) for n > 15. - Wesley Ivan Hurt, Aug 10 2016
E.g.f.: x*(2 +16894*x +2384431*x^2 +42390055*x^3 +210809445*x^4 + 420716100*x^5 +408747213*x^6 +216628590*x^7 +67128535*x^8 +12662651*x^9 +1479478*x^10 +106470*x^11 +4550*x^12 +105*x^13 +x^14)*exp(x)/2. - G. C. Greubel, Oct 11 2019

A170799 a(n) = n^10*(n^7 + 1)/2.

Original entry on oeis.org

0, 1, 66048, 64599606, 8590458880, 381474609375, 8463359955456, 116315398231228, 1125900443713536, 8338592593225485, 50000005000000000, 252723527218359186, 1109305584328900608, 4325208028619914891, 15245673509292925440, 49263062956171875000, 147573953139432226816
Offset: 0

Views

Author

N. J. A. Sloane, Dec 11 2009

Keywords

Crossrefs

Sequences of the form n^10*(n^m + 1)/2: A170793 (m=1), A170794 (m=2), A170795 (m=3), A170796 (m=4), A170797 (m=5), A170798 (m=6), this sequence (m=7), A170800 (m=8), A170801 (m=9), A170802 (m=10).

Programs

  • GAP
    List([0..20], n-> n^10*(n^7 +1)/2); # G. C. Greubel, Oct 11 2019
  • Magma
    [n^10*(n^7+1)/2: n in [0..20]]; // Vincenzo Librandi, Aug 27 2011
    
  • Maple
    seq(n^10*(n^7 +1)/2, n=0..20); # G. C. Greubel, Oct 11 2019
  • Mathematica
    Table[n^10(n^7+1)/2,{n,0,20}] (* Harvey P. Dale, Aug 27 2013 *)
  • PARI
    vector(21, m, (m-1)^10*((m-1)^7 + 1)/2) \\ G. C. Greubel, Oct 11 2019
    
  • Sage
    [n^10*(n^7 +1)/2 for n in (0..20)] # G. C. Greubel, Oct 11 2019
    

Formula

G.f.: x*(65024*x^15 + 63370125*x^14 + 7437628950*x^13 + 236677103915*x^12 + 2858645957220*x^11 + 15527824213413*x^10 + 41568614867330*x^9 + 57445190329275*x^8 + 41568608318040*x^7 + 15527828734975*x^6 + 2858646015162*x^5 + 236676197145*x^4 + 7437770500*x^3 + 63410895*x^2 + 66030*x + 1)/(x-1)^18. - Colin Barker, Feb 24 2013
E.g.f.: x*(2 + 66046*x + 21467155*x^2 + 694371395*x^3 + 5652794176*x^4 + 17505772725*x^5 + 25708110666*x^6 + 20415995778*x^7 + 9528822348*x^8 + 2758334151*x^9 + 512060978*x^10 + 62022324*x^11 + 4910178*x^12 + 249900*x^13 + 7820*x^14 + 136*x^15 + x^16)*exp(x)/2. - G. C. Greubel, Oct 12 2019

A170800 a(n) = n^10*(n^8 + 1)/2.

Original entry on oeis.org

0, 1, 131584, 193739769, 34360262656, 1907353515625, 50780008567296, 814206940192849, 9007199791611904, 75047319391891761, 500000005000000000, 2779958669714828041, 13311666671401304064, 56227703544907942489
Offset: 0

Views

Author

N. J. A. Sloane, Dec 11 2009

Keywords

Crossrefs

Sequences of the form n^10*(n^m + 1)/2: A170793 (m=1), A170794 (m=2), A170795 (m=3), A170796 (m=4), A170797 (m=5), A170798 (m=6), A170799 (m=7), this sequence (m=8), A170801 (m=9), A170802 (m=10).

Programs

  • GAP
    List([0..20], n-> n^10*(n^8 +1)/2); # G. C. Greubel, Oct 11 2019
  • Magma
    [n^10*(n^8+1)/2: n in [0..20]]; // Vincenzo Librandi, Aug 27 2011
    
  • Maple
    seq(n^10*(n^8 +1)/2, n=0..20); # G. C. Greubel, Oct 11 2019
  • Mathematica
    Table[n^10 (n^8+1)/2,{n,0,20}] (* Harvey P. Dale, Jul 14 2013 *)
  • PARI
    vector(21, m, (m-1)^10*((m-1)^8 + 1)/2) \\ G. C. Greubel, Oct 11 2019
    
  • Sage
    [n^10*(n^8 +1)/2 for n in (0..20)] # G. C. Greubel, Oct 11 2019
    

Formula

G.f.: x*(1 + 131565*x + 191239844*x^2 + 30701706940*x^3 + 1287510524640*x^4 + 20228672856392*x^5 + 142998539385460*x^6 + 503354978422188*x^7 + 932692832164970*x^8 + 932692832164970*x^9 + 503354978422188*x^10 + 142998539385460*x^11 + 20228672856392*x^12 + 1287510524640*x^13 + 30701706940*x^14 +191239844*x^15 + 131565*x^16 + x^17)/(1-x)^19. - Harvey P. Dale, Jul 14 2013
E.g.f.: x*(2 + 131582*x + 64448340*x^2 + 2798841090*x^3 + 28958138070*x^4 + 110687273866*x^5 + 197462489280*x^6 + 189036065760*x^7 + 106175395800*x^8 + 37112163804*x^9 + 8391004908*x^10 + 1256328866*x^11 + 125854638*x^12 + 8408778*x^13 + 367200*x^14 + 9996*x^15 + 153*x^16 + x^17)*exp(x)/2. - G. C. Greubel, Oct 12 2019

A170796 a(n) = n^10*(n^4 + 1)/2.

Original entry on oeis.org

0, 1, 8704, 2421009, 134742016, 3056640625, 39212315136, 339252774049, 2199560126464, 11440139619681, 50005000000000, 189887885503921, 641990190956544, 1968757122095569, 5556148040106496, 14596751337890625
Offset: 0

Views

Author

N. J. A. Sloane, Dec 11 2009

Keywords

Crossrefs

Sequences of the form n^10*(n^m + 1)/2: A170793 (m=1), A170794 (m=2), A170795 (m=3), this sequence (m=4), A170797 (m=5), A170798 (m=6), A170799 (m=7), A170800 (m=8), A170801 (m=9), A170802 (m=10).

Programs

  • GAP
    List([0..20], n-> n^10*(n^4 +1)/2); # G. C. Greubel, Oct 11 2019
  • Magma
    [n^10*(n^4+1)/2: n in [0..20]]; // Vincenzo Librandi, Aug 26 2011
    
  • Maple
    seq(n^10*(n^4 +1)/2, n=0..20); # G. C. Greubel, Oct 11 2019
  • Mathematica
    Table[n^10*(n^4 +1)/2, {n,0,20}] (* G. C. Greubel, Oct 11 2019 *)
  • PARI
    vector(21, m, (m-1)^10*((m-1)^4 + 1)/2) \\ G. C. Greubel, Oct 11 2019
    
  • Sage
    [n^10*(n^4 +1)/2 for n in (0..20)] # G. C. Greubel, Oct 11 2019
    

Formula

From G. C. Greubel, Oct 11 2019: (Start)
G.f.: x*(1 +8689*x +2290554*x^2 +99340346*x^3 +1285757375*x^4 +6420936303*x^5 +13986239532*x^6 +13986239532*x^7 +6420936303*x^8 +1285757375*x^9 +99340346*x^10 +2290554*x^11 +8689*x^12 +x^13)/(1-x)^15.
E.g.f.: x*(2 +8702*x +798300*x^2 +10425850*x^3 +40117560*x^4 +63459200*x^5 +49335160*x^6 +20913070*x^7 +5135175*x^8 +752753*x^9 + 66066*x^10 +3367*x^11 +91*x^12 +x^13)*exp(x)/2. (End)
Showing 1-7 of 7 results.