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 1-10 of 12 results. Next

A135799 Second column (k=1) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 4, 5, 48, 252, 1832, 14625, 132080, 1323168, 14576076, 175108661, 2278429216, 31920719820, 479088848976, 7669098865441, 130426934203296, 2348478878321248, 44633950190867220, 892899715052136645
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008, Feb 22 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+1} with exactly one successor pair (i,i+1). Due to cyclicity also (n+1,1) is a successor pair.
The o.g.f. of this sequence seems to be the product of the o.g.f. for A000166 (derangements) by the fraction (1+2*x)/(1+x)^2 = 1 - x^2+ 2*x^3 - 3*x^4 + ... = 1 + sum( (-1)^i i x^(i+1), i=0..infinity) - Thomas Baruchel, Jan 08 2016
This correspond to the following transform: a(n) = b(n) - sum((-1)^(n + i) (n - i - 1)*b(i), (i=0..n-2)) - Olivier Gérard, Mar 05 2016

Examples

			a(3)=4 because the 4!/4 = 6 circular permutations of n=4 elements (1,2,3,4), (1,4, 3,2), (1,3,4,2),(1,2,4,3), (1,4,2,3) and (1,3,2,4) have 4,0,1,1, 1 and 1 successor pair(s), respectively.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=1.

Crossrefs

Cf. A000757 (k=0 column), A134515 (k=2 column).

Programs

  • Mathematica
    f[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := f[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[a[n, 1], {n, 21}] (* Michael De Vlieger, Jan 09 2016, after Jean-François Alcover at A134832 *)

Formula

a(n) = (n+1)*A000757(n), n>=0.
E.g.f.: (d/dx) x*(1-log(1-x))/e^x.
O.g.f.: see comment section.

A135802 Fifth column (k=4) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 35, 70, 1008, 7560, 75570, 804375, 9443720, 120408288, 1658028645, 24515212540, 387332966720, 6511826843280, 116059273664436, 2185693176650685, 43366955622595920, 904164368153680480
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008, Feb 22 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+4} with exactly four successor pairs (i,i+1). Due to cyclicity also (n+4,1) is a successor pair.

Examples

			a(0)=1 because the 4!/4 = 6 circular permutations of n=4 elements (1,2,3,4), (1,4,3,2), (1,3,4,2),(1,2,4,3), (1,4,2,3) and (1,3,2,4) have 4,0,1,1,1 and 1 successor pair, respectively. Hence (1,2,3,4) is the only circular permutation with 4 successors.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=4.

Crossrefs

Cf. A135801 (column k=3), A135803 (column k=5).

Programs

  • Mathematica
    f[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := f[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[a[n, 4], {n, 4, 25}] (* G. C. Greubel, Nov 10 2016 *)

Formula

a(n) = binomial(n+4,4)*A000757(n), n>=0.
E.g.f.: (d^4/dx^4) (x^4/4!)*(1-log(1-x))/e^x.

A135803 Sixth column (k=5) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 56, 126, 2016, 16632, 181368, 2091375, 26442416, 361224864, 5305691664, 83351722636, 1394398680192, 24744942004464, 464237094657744, 9179911341932877, 190814604739422048, 4159156093506930208
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+5} with exactly five successor pairs (i,i+1). Due to cyclicity also (n+5,1) is a successor pair.

Examples

			a(0)=1 because from the 5!/5 = 24 circular permutations of n=5 elements only one, namely (1,2,3,4,5), has five successors.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=5.

Crossrefs

Cf. A135802 (column k=4), A135804 (column k=6).

Programs

  • Mathematica
    f[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := f[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[a[n, 5], {n, 5, 25}] (* G. C. Greubel, Nov 10 2016 *)

Formula

a(n) = binomial(n+5,5)*A000757(n), n>=0.
E.g.f.: (d^5/dx^5) (x^5/5!)*(1-log(1-x))/e^x.

A135804 Seventh column (k=6) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 84, 210, 3696, 33264, 392964, 4879875, 66106040, 963266304, 15032793048, 250055167908, 4415595820608, 82483140014880, 1624829831302104, 33659674920420549, 731455984834451184, 16636624374027720832
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+6} with exactly six successor pairs (i,i+1). Due to cyclicity also (n+6,1) is a successor pair.

Examples

			a(0)=1 because from the 6!/6 = 120 circular permutations of n=6 elements only one, namely (1,2,3,4,5,6), has six successors.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=6.

Crossrefs

Cf. A135803 (column k=5), A135805 (column k=7).

Programs

  • Mathematica
    f[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := f[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[a[n, 6], {n, 6, 25}] (* G. C. Greubel, Nov 10 2016 *)

Formula

a(n) = binomial(n+6,6)*A000757(n), n>=0.
E.g.f.: (d^6/dx^6) (x^6/6!)*(1-log(1-x))/e^x.

A135805 Eighth column (k=7) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 120, 330, 6336, 61776, 785928, 10456875, 151099520, 2339361024, 38655753552, 678721170036, 12615988058880, 247449420044640, 5106608041235184, 110596074738524661, 2507849090860975488
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+7} with exactly seven successor pairs (i,i+1). Due to cyclicity also (n+7,1) is a successor pair.

Examples

			a(0)=1 because from the 7!/7 = 720 circular permutations of n=7 elements only one, namely (1,2,3,4,5,6,7), has seven successors.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=7.

Crossrefs

Cf. A135804 (column k=6), A135806 (column k=8).

Programs

  • Mathematica
    f[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := f[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[a[n, 7], {n, 7, 25}] (* G. C. Greubel, Nov 10 2016 *)

Formula

a(n) = binomial(n+7,7)*A000757(n), n>=0.
E.g.f.: (d^7/dx^7) (x^7/7!)*(1-log(1-x))/e^x.

A135806 Ninth column (k=8) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 165, 495, 10296, 108108, 1473615, 20913750, 321086480, 5263562304, 91807414686, 1696802925090, 33116968654560, 680485905122760, 14681498118551154, 331788224215573983, 7837028408940548400
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+8} with exactly eight successor pairs (i,i+1). Due to cyclicity also (n+8,1) is a successor pair.

Examples

			a(0)=1 because from the 8!/8 = 5040 circular permutations of n=8 elements only one, namely (1,2,3,4,5,6,7,8), has eight successors.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=8.

Crossrefs

Cf. A135805 (column k=7), A135807 (column k=9).

Programs

  • Mathematica
    f[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := f[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[a[n, 8], {n, 8, 25}] (* G. C. Greubel, Nov 10 2016 *)

Formula

a(n) = binomial(n+8,8)*A000757(n), n>=0.
E.g.f.: (d^8/dx^8) (x^8/8!)*(1-log(1-x))/e^x.

A135808 Numerator of z-sequence for the Sheffer (Appell type) triangle A134832 (circular succession numbers).

Original entry on oeis.org

0, 0, 1, 1, 8, 8, 159, 659, 6824, 4668, 517581, 4941685, 61043344, 367628164, 10269016939, 147207286503, 2322683458544, 19149119743336, 677630804946393, 2516289402924117, 247342217288517496, 2548438247219028464
Offset: 0

Views

Author

Wolfdieter Lang, Dec 06 2007

Keywords

Comments

The denominators are given in A126352.
For the a- and z-sequences of Sheffer triangles see the W. Lang link under A006232.

Examples

			Rationals r(n)=[0,0,1/3, 1/4, 8/5, 8/3, 159/7, 659/8, 6824/9, 4668, 517581/11,...].
		

Crossrefs

Cf. A126352 (denominators), A134832.

Formula

a(n) = denominator(r(n)) with the rationals r(n) from the given e.g.f.
E.g.f. for rationals r(n): (1-exp(x)/(1-log(1-x)))/x.

A134515 Third column (k=2) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 10, 15, 168, 1008, 8244, 73125, 726440, 7939008, 94744494, 1225760627, 17088219120, 255365758560, 4072255216296, 69021889788969, 1239055874931312, 23484788783212480, 468656477004105810, 9821896865573503095
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008, Feb 22 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+2} with exactly two successor pairs (i,i+1). Due to cyclicity also (n+2,1) is a successor pair.

Examples

			a(2)=0 because the 4!/4 = 6 circular permutations of n=4 elements (1,2,3,4), (1,4,3,2), (1,3,4,2),(1,2,4,3), (1,4,2,3) and (1,3,2,4) have 4,0,1,1,1 and 1 successor pair, respectively.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=2.

Crossrefs

Cf. A135799 (column k=1).

Formula

E.g.f.: (d^2/dx^2) (x^2/2!)*(1-log(1-x))/e^x.
a(n) = (((n+2)*(n+1))/2)*A000757(n), n>=0.

A134833 Alternating row sums of triangle A134832.

Original entry on oeis.org

1, -1, 1, 0, -2, 12, -16, 144, 368, 4768, 39488, 412288, 4577280, 55671808, 731390976, 10335518720, 156303439872, 2518984822784, 43099089166336, 780268880543744, 14902336357040128, 299452809649520640, 6315501510334480384, 139485953831272710144, 3219718099932104622080
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008

Keywords

Crossrefs

Cf. A000142 (factorials as row sums of triangle A134832).

Programs

  • Mathematica
    A000757[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := A000757[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[Sum[a[n, k]*(-1)^k, {k, 0, n}], {n, 0, 10}] (* G. C. Greubel, Nov 10 2016 *)

Formula

a(n) = Sum_{k=0..n} A134832(n,k)*(-1)^k for n>=0.

A135801 Fourth column (k=3) of triangle A134832 (circular succession numbers).

Original entry on oeis.org

1, 0, 0, 20, 35, 448, 3024, 27480, 268125, 2905760, 34402368, 442140972, 6128803135, 91137168640, 1447072631840, 24433531297776, 437138635330137, 8260372499542080, 164393521482487360, 3436814164696775940
Offset: 0

Views

Author

Wolfdieter Lang, Jan 21 2008, Feb 22 2008

Keywords

Comments

a(n) enumerates circular permutations of {1,2,...,n+3} with exactly three successor pairs (i,i+1). Due to cyclicity also (n+3,1) is a successor pair.

Examples

			a(1)=0 because the 4!/4 = 6 circular permutations of n=4 elements (1,2,3,4), (1,4,3,2), (1,3,4,2),(1,2,4,3), (1,4,2,3) and (1,3,2,4) have 4,0,1,1,1 and 1 successor pair, respectively.
		

References

  • Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC, Boca Raton, Florida, 2002, p. 183, eq. (5.15), for k=3.

Crossrefs

Cf. A134515 (column k=2), A135802 (column k=4).

Programs

  • Mathematica
    f[n_] := (-1)^n + Sum[(-1)^k*n!/((n - k)*k!), {k, 0, n - 1}]; a[n_, n_] = 1; a[n_, 0] := f[n]; a[n_, k_] := a[n, k] = n/k*a[n - 1, k - 1]; Table[a[n, 3], {n, 3, 10}] (* G. C. Greubel, Nov 10 2016 *)

Formula

a(n) = binomial(n+3,3)*A000757(n), n>=0.
E.g.f.: (d^3/dx^3) (x^3/3!)*(1-log(1-x))/e^x.
Showing 1-10 of 12 results. Next