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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A059332 Determinant of n X n matrix A defined by A[i,j] = (i+j-1)! for 1 <= i,j <= n.

Original entry on oeis.org

1, 1, 2, 24, 3456, 9953280, 859963392000, 3120635156889600000, 634153008009974906880000000, 9278496603801318870491332608000000000, 12218100099725239100847669366019325952000000000000, 1769792823810713244721831122736499011207487815680000000000000000
Offset: 0

Views

Author

Noam Katz (noamkj(AT)hotmail.com), Jan 26 2001

Keywords

Comments

Hankel transform of n! (A000142(n)) and of A003319. - Paul Barry, Oct 07 2008
Hankel transform of A000255. - Paul Barry, Apr 22 2009
Monotonic magmas of size n, i.e., magmas with elements labeled 1..n where product(i,j) >= max(i,j). - Chad Brewbaker, Nov 03 2013
Also called the bouncing factorial function. - Alexander Goebel, Apr 08 2020

Examples

			a(4) = 3456 because the relevant matrix is {1 2 6 24 / 2 6 24 120 / 6 24 120 720 / 24 120 720 5040 } and the determinant is 3456.
		

Crossrefs

Cf. A162014 and A055209. - Johannes W. Meijer, Jun 27 2009

Programs

  • Maple
    with(linalg): Digits := 500: A059332 := proc(n) local A, i, j: A := array(1..n,1..n): for i from 1 to n do for j from 1 to n do A[i,j] := (i+j-1)! od: od: RETURN(det(A)) end: for n from 1 to 20 do printf(`%d,`, A059332(n)) od;
    # second Maple program:
    a:= proc(n) option remember;
          `if`(n=0, 1, a(n-1)*n!^2/n)
        end:
    seq(a(n), n=0..12);  # Alois P. Heinz, Apr 29 2020
  • Mathematica
    Table[n! BarnesG[n+1]^2, {n, 1, 10}] (* Jean-François Alcover, Sep 19 2016 *)
  • PARI
    A059332(n)=matdet(matrix(n,n,i,j,(i+j-1)!)) \\ M. F. Hasler, Nov 03 2013
    
  • PARI
    a(n) = 2^binomial(n,2)*prod(k=1,n-1, binomial(k+2,2)^(n-1-k)) \\ Ralf Stephan, Nov 04 2013
  • Ruby
    def mono_choices(a,b,n)
        n - [a,b].max
    end
    def all_mono_choices(n)
        accum =1
        0.upto(n-1) do |i|
            0.upto(n-1) do |j|
                accum = accum * mono_choices(i,j,n)
            end
        end
        accum
    end
    1.upto(12) do |k|
    puts all_mono_choices(k)
    end # Chad Brewbaker, Nov 03 2013
    

Formula

a(n) = a(n-1)*(n!)*(n-1)! for n >= 2 so a(n) = product k=1, 2, ..., n k!*(k-1)!.
a(n) = 2^C(n,2)*Product_{k=1..(n-1), C(k+2,2)^(n-1-k)}. - Paul Barry, Jan 15 2009
a(n) = n!*product(k!, k=0..n-1)^2. - Johannes W. Meijer, Jun 27 2009
a(n) ~ (2*Pi)^(n+1/2) * exp(1/6 - n - 3*n^2/2) * n^(n^2 + n + 1/3) / A^2, where A = A074962 is the Glaisher-Kinkelin constant. - Vaclav Kotesovec, Aug 01 2015

Extensions

More terms from James Sellers, Jan 29 2001
Offset corrected. Comment and formula aligned with new offset by Johannes W. Meijer, Jun 24 2009
a(0)=1 prepended by Alois P. Heinz, Apr 08 2020

A162014 Sequence related to the o.g.f.s. of the right hand columns of the EG1 triangle A162005.

Original entry on oeis.org

1, 8, -1536, -14155776, 10436770529280, 923378661099307008000, -13724698564186788948502118400000, -45695540009113634492156662349750599680000000
Offset: 1

Views

Author

Johannes W. Meijer, Jun 27 2009

Keywords

Comments

The a(n) are the sums of the coefficients of the polynomials that appear in the numerators of the o.g.f.s. of the right hand columns of the EG1 triangle A162005, see the examples.

Examples

			The polynomials in the numerators of the first few o.g.f.s are:
numer(GF(1)) = 1
numer(GF(2)) = 2+6*z
numer(GF(3)) = 16+296*z-768*z^2-1080*z^3
numer(GF(4)) = 272+17376*z-321360*z^2-1298624*z^3+8914800*z^4-11262240*z^5-10206000*z^6
numer(GF(5)) = 7936 + 1305088*z - 79792256*z^2 - 109331968*z^3 + 41828672000*z^4-460917924352*z^5 + 238697445120*z^6 + 5066784271872*z^7 - 14723693948160*z^8+ 12172737024000*z^9 + 8101522800000*z^10
		

Crossrefs

A000012, A004004 (2x), A162008, A162009 and A162010 are the first five right hand columns of the EG1 triangle A162005.
Cf. A055209 and A059332.

Formula

a(n) = (-1)^( (n^2+n-2)/2)*4^((n-1)*n/2)*n!*product(k!, k=0..n-1)^2

A239350 Superprimorials squared.

Original entry on oeis.org

1, 4, 144, 129600, 5715360000, 30497732496000000, 27502882612852046400000000, 7167813920637790505994548640000000000, 674376505248717910810215697948155164304000000000000, 33564007734235791949707248640534383334045138980782017600000000000000
Offset: 0

Views

Author

Jonathan Sondow, Mar 22 2014

Keywords

Comments

Square of product of first n primorials = A006939(n)^2.
Smallest number with n distinct even exponents in its prime factorization.
The prime version of Ramanujan's infinite nested radical 1*sqrt(1+2*sqrt(1+3*sqrt(1+...))) is 2*sqrt(1+3*sqrt(1+5*sqrt(1+...))) = sqrt(4+sqrt(144+sqrt(129600+...))) = sqrt(a(1)+sqrt(a(2)+sqrt(a(3)+...))). See A239349 and A055209.

Crossrefs

Programs

  • Mathematica
    Rest[FoldList[Times, 1, FoldList[Times, 1, Prime[Range[9]]^2]]]

Formula

a(n) = Product_{k=1..n} A002110(k)^2 = Product_{k=1..n} prime(k)^(2(n-k+1)).

A100685 Powers of factorials A000142.

Original entry on oeis.org

1, 2, 4, 6, 8, 16, 24, 32, 36, 64, 120, 128, 216, 256, 512, 576, 720, 1024, 1296, 2048, 4096, 5040, 7776, 8192, 13824, 14400, 16384, 32768, 40320, 46656, 65536, 131072, 262144, 279936, 331776, 362880, 518400, 524288, 1048576, 1679616, 1728000
Offset: 1

Views

Author

Kyle Schalm and Jonathan Sondow, Dec 08 2004

Keywords

Comments

Subsequence of A001013. Supersequence of A036740 without its first term.
Supersequence also of A046882 and A055209 without their first terms. - Jonathan Sondow and Robert G. Wilson v, Dec 19 2004

Examples

			24 = (4!)^1 and 36 = (3!)^2.
		

Crossrefs

Cf. also A046882 and A055209.
Subsequences: A000079, A000400, A009968.

Programs

  • Mathematica
    With[{ln = Log[10!]}, Table[With[{f = m!}, Table[f^j, {j, 0, Floor[ln/Log[f]]}]], {m, 2, 10}]] //Flatten //Union

Formula

Sum_{n>=1} 1/a(n) = 1 + A331373. - Amiram Eldar, Nov 21 2021

A101800 a(n)= abs(det[A000166(i+j+1)]), i,j=0...n, is the absolute value of the Hankel determinant of order n+1 of the derangements numbers, cf. A000166.

Original entry on oeis.org

0, 1, 16, 2160, 4644864, 220962816000, 126311423016960000, 97655159393202733056000000, 2873961139404949958783139840000000000, 5118723340142578530942677236206891171840000000000
Offset: 0

Views

Author

Karol A. Penson, Dec 17 2004

Keywords

Comments

a(n) = abs(product( (p!)^2,p=0..n )*(n+1)!*LaguerreL(n+1,0,1)), n=0,1..., where LaguerreL(n,lambda,x) are generalized Laguerre polynomial.

Crossrefs

Programs

  • Mathematica
    a[n_] := Table[Subfactorial[i+j+1], {i, 0, n}, {j, 0, n}] // Det // Abs;
    Table[a[n], {n, 0, 9}] (* Jean-François Alcover, Aug 18 2024 *)

Formula

a(n) = abs(A055209(n)*A009940(n+1)). [corrected by Vaclav Kotesovec, Feb 25 2019]

A136411 a(n) = Product_{k=1..n} (2*k-1)^(2*n-2*k+1).

Original entry on oeis.org

1, 3, 135, 212625, 21097715625, 207248662456171875, 291128066470548703880859375, 79746389028864195813528714933837890625, 5570294521107277357810167397301815834831695556640625
Offset: 1

Views

Author

Ctibor O. Zizka, Mar 31 2008

Keywords

Crossrefs

Programs

  • Magma
    [(&*[(2*k-1)^(2*n-2*k+1): k in [1..n]]): n in [1..10]]; // G. C. Greubel, Oct 14 2018
  • Mathematica
    Table[Product[(2*k - 1)^(2*n - 2*k + 1), {k, 1, n}], {n, 1, 10}] (* Stefan Steinerberger, May 18 2008 *)
    sf[n_] := BarnesG[n + 2]; a[n_] := sf[2 n - 1]/(2^(n (n - 1)) sf[n - 1]^2); Table[a[n], {n, 1, 10}]  (* Robert Coquereaux, Apr 02 2013 *)
  • PARI
    a(n) = prod(k=1, n, (2*k-1)^(2*n-2*k+1)) \\ Anders Hellström, Sep 16 2015
    

Formula

a(n) = A107254(n) / 2^(n*(n - 1)).
a(n) = sf(2*n-1) / (2^(n*(n-1)) * sf(n-1)^2), n >= 1, where sf(n) = BarnesG(n + 2) is the superfactorial defined in A000178. - Robert Coquereaux, Apr 02 2013
a(n) ~ A * 2^(n^2 + n - 1/12) * n^(n^2 + 1/12) / exp(3*n^2/2 + 1/12), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant. - Vaclav Kotesovec, Jul 10 2015

Extensions

More terms from Stefan Steinerberger, May 18 2008

A136807 Hankel transform of double factorial numbers n!*2^n=A000165(n).

Original entry on oeis.org

1, 4, 256, 589824, 86973087744, 1282470362637926400, 2723154477021188283432960000, 1133321924829207204666583887642624000000, 120746421332702772771144114237731253721340313600000000
Offset: 0

Views

Author

Paul Barry, Jan 23 2008

Keywords

Comments

By the properties of the Hankel transform, a(n)=2^(n(n+1))*A055209(n).
Also Hankel transform of A000354, A010844, A082032. - Philippe Deléham, Jan 23 2008

Crossrefs

Programs

  • Magma
    [1] cat [(&*[(2*k)^(2*(n-k+1)): k in [1..n]]): n in [1..10]]; // G. C. Greubel, Oct 14 2018
  • Mathematica
    Table[Product[(2k)^(2(n-k+1)),{k,n}],{n,0,10}] (* Harvey P. Dale, Apr 11 2013 *)
  • PARI
    for(n=0,10, print1(prod(k=1,n,(2*k)^(2*(n-k+1))), ", ")) \\ G. C. Greubel, Oct 14 2018
    

Formula

a(n) = Product_{k=1..n} (2k)^(2(n-k+1)).
a(n) ~ 2^((n+1)^2) * Pi^(n+1) * n^(n^2 + 2*n + 5/6) / (A^2 * exp(3*n^2/2 + 2*n - 1/6)), where A is the Glaisher-Kinkelin constant A074962. - Vaclav Kotesovec, Feb 24 2019

A290770 a(n) = Product_{k=1..n} k^(2*k).

Original entry on oeis.org

1, 1, 16, 11664, 764411904, 7464960000000000, 16249593066946560000000000, 11020848942410302096869949440000000000, 3102093199396597590886754340698424229232640000000000, 465607547420733489126893933985879279492195953053596584509440000000000
Offset: 0

Views

Author

Ilya Gutkovskiy, Aug 10 2017

Keywords

Crossrefs

Programs

  • Magma
    [1] cat [(&*[k^(2*k): k in [1..n]]): n in [1..10]]; // G. C. Greubel, Oct 14 2018
  • Mathematica
    Table[Product[k^(2 k), {k, 1, n}], {n, 0, 9}]
    Table[Hyperfactorial[n]^2, {n, 0, 9}]
    Table[n!^(2 n)/BarnesG[n + 1]^2, {n, 0, 9}]
  • PARI
    a(n) = prod(k=1, n, k^(2*k)) \\ Felix Fröhlich, Aug 10 2017
    

Formula

a(n) = A002109(n)^2.
a(n) = A185141(n)/A000178(n-1)^2 for n > 0.
a(n) = (n!)^(2*n)/G(n+1)^2, where G() is the Barnes G-function.
a(n) ~ A^2*exp(-n^2/2)*n^(n*(n+1))*n^(1/6), where A is the Glaisher-Kinkelin constant (A074962).

A067736 Decimal expansion of exp(3/2).

Original entry on oeis.org

4, 4, 8, 1, 6, 8, 9, 0, 7, 0, 3, 3, 8, 0, 6, 4, 8, 2, 2, 6, 0, 2, 0, 5, 5, 4, 6, 0, 1, 1, 9, 2, 7, 5, 8, 1, 9, 0, 0, 5, 7, 4, 9, 8, 6, 8, 3, 6, 9, 6, 6, 7, 0, 5, 6, 7, 7, 2, 6, 5, 0, 0, 8, 2, 7, 8, 5, 9, 3, 6, 6, 7, 4, 4, 6, 6, 7, 1, 3, 7, 7, 2, 9, 8, 1, 0, 5, 3, 8, 3, 1, 3, 8, 2, 4, 5, 3, 3, 9, 1, 3, 8, 8, 6, 1
Offset: 1

Views

Author

Alford Arnold, Mar 10 2002

Keywords

Comments

It is well known that derangements, A000166, are related to exp(1) (cf. A001113). It appears that derangements with minimal cycle size 3 relate to exp(1+1/2). for example, 720/160 = 4.5, 5040/1140 = 4.4210, 40320/8988 = 4.4859, 362880/80864 = 4.4875 the pattern continues - derangements with minimal cycle size 4 appear to relate in the same way to exp(1 + 1/2 +1/3).

Examples

			4.4816890703380648226020554601192758190057498683696...
		

Crossrefs

Programs

Formula

Equals lim_{n->oo} n/A055209(n)^(1/n^2) (Bătinetu-Giurgiu, 2016). - Amiram Eldar, Apr 11 2022
Solution of x = Integral_{t=0..x} log(t^2) dt. - Thomas Scheuerle, Sep 22 2023

Extensions

More terms from Sascha Kurz, Mar 19 2002

A091810 Hankel transform of the sequence A001469 (unsigned), Genocchi numbers of first kind.

Original entry on oeis.org

1, 2, 96, 497664, 825564856320, 1027134771639091200000, 1932215036193527461576704000000000, 9973959265081827837426668870219857920000000000000
Offset: 0

Views

Author

Philippe Deléham, Mar 07 2004

Keywords

Comments

This sequence is the Hankel transform (see A001906 for definition)of the sequence defined by, for n>=0, a(n) = |A001469(n+1)|; example: det([1, 1, 3, 17; 1, 3, 17, 155; 3, 17, 155, 2073; 17, 155, 2073, 38227]) = 497664 = 4!*12^4.

Crossrefs

Programs

  • Magma
    [Factorial(n+1)*(&*[(Factorial(k))^2: k in [0..n]])^2: n in [0..10]]; // G. C. Greubel, Oct 14 2018
  • Mathematica
    Table[(n + 1)!*BarnesG[n + 2]^4, {n, 0, 10}] (* G. C. Greubel, Oct 14 2018 *)
  • PARI
    for(n=0,10, print1((n+1)!*(prod(k=0,n, (k!)^2))^2, ", ")) \\ G. C. Greubel, Oct 14 2018
    

Formula

a(n) = (n+1)!*A000178(n)^4 = (n+1)!*A055209(n)^2.
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