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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A158432 Number of permutations of 1..n containing the relative rank sequence { 45312 } at any spacing.

Original entry on oeis.org

1, 26, 458, 6996, 101072, 1438112, 20598112, 300892896, 4521034917, 70286670034, 1135485759114, 19121776482564, 336412530327804, 6191800556586104, 119301546930406184, 2406376964044265344, 50786085223779295344, 1120447461653440780128, 25810064637612342838624
Offset: 5

Views

Author

R. H. Hardin, Mar 18 2009

Keywords

Comments

Same series for 54321 12345 45321 21345 12354 54312 34521 32145 12543 54123 23451 43215 15432 51234 21354 34512 32154 21543 45123.

Crossrefs

Programs

  • Maple
    h:= proc(l) local n; n:=nops(l); add(i, i=l)! /mul(mul(1+l[i]-j
          +add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n)
        end:
    g:= (n, i, l)-> `if`(n=0 or i=1, h([l[], 1$n])^2, `if`(i<1, 0,
                     add(g(n-i*j, i-1, [l[], i$j]), j=0..n/i))):
    a:= n-> n! -g(n, 4, []):
    seq(a(n), n=5..25);  # Alois P. Heinz, Jul 05 2012
    # second Maple program
    a:= proc(n) option remember; `if`(n<5, 0, `if`(n=5, 1,
         ((132-142*n-301*n^2-35*n^3+25*n^4+n^5)*a(n-1)
         -2*(10*n^3+33*n^2-181*n-2)*(n-1)^2*a(n-2)
         +64*(n-2)^2*(n-1)^3*a(n-3))/ ((n+4)*(n-5)*(n+3)^2)))
        end:
    seq(a(n), n=5..30);  # Alois P. Heinz, Sep 26 2012
  • Mathematica
    h[l_] := With[{n = Length[l]}, Sum[i, {i, l}]!/Product[Product[1+l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i+1, n}], {j, 1, l[[i]]}], {i, 1, n}]];
    g[n_, i_, l_] := If[n == 0 || i === 1, h[Join[l, Array[1 &, n]]]^2, If[i < 1, 0, Sum[g[n - i*j, i - 1, Join[l, Array[i &, j]]], {j, 0, n/i}]]];
    a[n_] := n! - g[n, 4, {}];
    Table[a[n], {n, 5, 25}] (* Jean-François Alcover, Jun 19 2018, after Alois P. Heinz's first program *)

Formula

a(n) = A214152(n,5) = A000142(n)-A047889(n) = A000142(n)-A214015(n,4).

Extensions

Extended beyond a(16) by Alois P. Heinz, Jul 05 2012

A072167 T_10(n) in the notation of Bergeron et al., u_10(n) in the notation of Gessel: Related to Young tableaux of bounded height.

Original entry on oeis.org

1, 2, 6, 24, 120, 720, 5040, 40320, 362880, 3628800, 39916799, 479001478, 6227012074, 87177809092, 1307651456625, 20921799763626, 355647213494682, 6400805686152436, 121585553747301448, 2430677026538811240
Offset: 1

Views

Author

Jesse Carlsson (j.carlsson(AT)physics.unimelb.edu.au), Jun 29 2002

Keywords

Comments

In general, column k > 1 of A214015 is asymptotic to (Product_{j=1..k} j!) * k^(2*n + k^2/2) / (Pi^((k-1)/2) * 2^((k-1)*(k+2)/2) * n^((k^2-1)/2)). - Vaclav Kotesovec, Sep 10 2014

Crossrefs

Cf. A052399 for T_6(n), A047890 for T_5(n), A047889 for T_4(n).
Column k=10 of A214015.

Programs

  • Maple
    h:= proc(l) local n; n:=nops(l); add(i, i=l)! / mul(mul(1+l[i]-j
           +add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n)
        end:
    g:= proc(n, i, l) option remember;
          `if`(n=0, h(l)^2, `if`(i<1, 0, `if`(i=1, h([l[], 1$n])^2,
           g(n, i-1, l)+ `if`(i>n, 0, g(n-i, i, [l[], i])))))
        end:
    a:= n-> g(n, 10, []):
    seq(a(n), n=0..25); # Vaclav Kotesovec, Sep 10 2014, after Alois P. Heinz
  • Mathematica
    RecurrenceTable[{-7372800*(-4 + n)^2*(-3 + n)^2*(-2 + n)^2*(-1 + n)^2*(15 + 2*n)*a[-5 + n] + 256*(-3 + n)^2*(-2 + n)^2*(-1 + n)^2*(11018760 + 4743323*n + 577824*n^2 + 21076*n^3)*a[-4 + n]-8*(-2 + n)^2*(-1 + n)^2*(2488711560 + 2208119423*n + 580006399*n^2 + 64938154*n^3 + 3273732*n^4 + 61160*n^5)*a[-3 + n] + 4*(-1 + n)^2*(8002290720 + 21962910556*n + 10433770264*n^2 + 2088552609*n^3 + 215646686*n^4 + 12084237*n^5 + 349536*n^6 + 4092*n^7)*a[-2 + n]-2*(-45705600000 + 64584000000*n + 68412531600*n^2 + 22314826244*n^3 + 3672058745*n^4 + 350428790*n^5 + 20286926*n^6 + 704088*n^7 + 13497*n^8 + 110*n^9)*a[-1 + n] + (9 + n)^2*(16 + n)^2*(21 + n)^2*(24 + n)^2*(25 + n)*a[n]==0,a[1]==1,a[2]==2,a[3]==6,a[4]==24,a[5]==120},a,{n,1,20}] (* Vaclav Kotesovec, Sep 10 2014 *)

Formula

a(n) ~ 546852789 * 2^(2*n + 26)* 5^(2*n + 55) / (n^(99/2) * Pi^(9/2)). - Vaclav Kotesovec, Sep 10 2014
Recurrence: (n+9)^2*(n + 16)^2*(n + 21)^2*(n + 24)^2*(n + 25)*a(n) = 2*(110*n^9 + 13497*n^8 + 704088*n^7 + 20286926*n^6 + 350428790*n^5 + 3672058745*n^4 + 22314826244*n^3 + 68412531600*n^2 + 64584000000*n - 45705600000)*a(n-1) - 4*(n-1)^2*(4092*n^7 + 349536*n^6 + 12084237*n^5 + 215646686*n^4 + 2088552609*n^3 + 10433770264*n^2 + 21962910556*n + 8002290720)*a(n-2) + 8*(n-2)^2*(n-1)^2*(61160*n^5 + 3273732*n^4 + 64938154*n^3 + 580006399*n^2 + 2208119423*n + 2488711560)*a(n-3) - 256*(n-3)^2*(n-2)^2*(n-1)^2*(21076*n^3 + 577824*n^2 + 4743323*n + 11018760)*a(n-4) + 7372800*(n-4)^2*(n-3)^2*(n-2)^2*(n-1)^2*(2*n + 15)*a(n-5). - Vaclav Kotesovec, Sep 10 2014

A141824 Antidiagonals of table A047888 (which counts longest increasing subsequences and pattern avoidances).

Original entry on oeis.org

1, 2, 4, 9, 24, 75, 269, 1095, 5039, 26084, 150356, 952526, 6553011, 48553418, 385693800, 3277413802, 29741002168, 287555932433, 2952769116993, 32079033571080, 367336668735826, 4419518218479215, 55733223965845539, 735448682261126767, 10142738983005750681
Offset: 1

Views

Author

Alford Arnold, Jul 08 2008

Keywords

Comments

Note that:
A000108 avoids string "123"
A005808 avoids string "1234"
A047889 avoids string "12345"
Note also that the left half and central diagonal of A047888 are partial sums of table A047874.

Examples

			We can write A141824(n) = 1 2 4 9 24 ... because A047888 begins
  1;
  1,  1;
  1,  2,  1;
  1,  5,  2,  1;
  1, 14,  6,  2,  1;
etc.
		

Crossrefs

Cf. A000108 (Catalan numbers), A005808, A047889, A047874.

Extensions

a(12)-a(25) from Alois P. Heinz, Apr 10 2012

A256200 Number of permutations in S_n that avoid the pattern 42351.

Original entry on oeis.org

1, 1, 2, 6, 24, 119, 694, 4580, 33252, 260204, 2161930, 18861307, 171341565, 1610345257, 15579644765, 154541844196, 1566713947713, 16190122718865, 170171678529883, 1816001425551270, 19646035298044543, 215179180467834605, 2383465957654163227, 26673704385975326866
Offset: 0

Views

Author

N. J. A. Sloane, Mar 19 2015

Keywords

Crossrefs

Representatives for the 16 Wilf-equivalence patterns of length 5 are given in A116485, A047889, and A256195-A256208.

Programs

  • Mathematica
    avoid[n_, pat_] := Module[{p1 = pat[[1]], p2 = pat[[2]], p3 = pat[[3]], p4 = pat[[4]], p5 = pat[[5]], lseq = {}, i, p,
        lpat = Subsets[(n + 1) - Range[n], {Length[pat]}],
        psn = Permutations[Range[n]]},
       For[i = 1, i <= Length[lpat], i++,
        p = lpat[[i]];
        AppendTo[lseq, Select[psn, MemberQ[#, {_, p[[p1]], _, p[[p2]], _, p[[p3]], _, p[[p4]], _, p[[p5]], _}, {0}] &]];
        ]; n! - Length[Union[Flatten[lseq, 1]]]];
    Table[avoid[n, {4, 2, 3, 5, 1}], {n, 0, 8}]  (* Robert Price, Mar 27 2020 *)

Formula

a(n) = n! - A158434(n). - Andrew Howroyd, May 18 2020

Extensions

a(14)-a(15) added by Andrew Howroyd, May 18 2020
More terms from Anthony Guttmann, Sep 29 2021

A224248 Number of permutations in S_n containing exactly one increasing subsequence of length 5.

Original entry on oeis.org

0, 0, 0, 0, 0, 1, 20, 270, 3142, 34291, 364462, 3844051, 40632886, 432715409, 4655417038, 50667480496, 558143676522, 6223527776874, 70228214538096, 801705888742781, 9254554670121572, 107975393459449243, 1272651313142352772, 15145990284267530992
Offset: 0

Views

Author

Brian Nakamura, Apr 02 2013

Keywords

References

  • B. Nakamura and D. Zeilberger, Using Noonan-Zeilberger Functional Equations to enumerate (in Polynomial Time!) Generalized Wilf classes, Adv. in Appl. Math. 50 (2013), 356-366.

Crossrefs

Programs

  • Maple
    # programs can be obtained from the Nakamura and Zeilberger link.

A248900 Number of permutations of [n] avoiding patterns 2431 and 54321.

Original entry on oeis.org

1, 1, 2, 6, 23, 102, 492, 2492, 13003, 69172, 372963, 2031174, 11148948, 61588814, 342068774, 1908740089, 10694374242, 60137305751, 339276548456, 1919787554118, 10892575241125, 61957028188350, 353224194632459, 2018076850631391, 11552829351121139, 66259093178740462
Offset: 0

Views

Author

Nathaniel Shar, Mar 06 2015

Keywords

Examples

			a(4) = 23 because all permutations of length 4 except 2431 lie in this set.
		

Crossrefs

A256196 Number of permutations in S_n that avoid the pattern 31524.

Original entry on oeis.org

1, 1, 2, 6, 24, 119, 694, 4579, 33216, 259401, 2147525, 18632512, 167969934, 1563027614, 14937175825, 146016423713, 1455402205257, 14753501614541, 151783381341695, 1582029822426003, 16681492660789425, 177726496203056670, 1911230701872865231, 20726637978574528119
Offset: 0

Views

Author

N. J. A. Sloane, Mar 19 2015

Keywords

Crossrefs

Representatives for the 16 Wilf-equivalence patterns of length 5 are given in A116485, A047889, and A256195-A256208.
Cf. A099952.

Programs

  • Mathematica
    avoid[n_, pat_] := Module[{p1 = pat[[1]], p2 = pat[[2]], p3 = pat[[3]], p4 = pat[[4]], p5 = pat[[5]], lseq = {}, i, p,
        lpat = Subsets[(n + 1) - Range[n], {Length[pat]}],
        psn = Permutations[Range[n]]},
       For[i = 1, i <= Length[lpat], i++,
        p = lpat[[i]];
        AppendTo[lseq, Select[psn, MemberQ[#, {_, p[[p1]], _, p[[p2]], _, p[[p3]], _, p[[p4]], _, p[[p5]], _}, {0}] &]];
        ]; n! - Length[Union[Flatten[lseq, 1]]]];
    Table[avoid[n, {3, 1, 5, 2, 4}], {n, 0, 8}]  (* Robert Price, Mar 27 2020 *)

Extensions

a(14)-a(16) from Bert Dobbelaere, Mar 18 2021
More terms from Anthony Guttmann, Sep 29 2021

A256197 Number of permutations in S_n that avoid the pattern 35214.

Original entry on oeis.org

1, 1, 2, 6, 24, 119, 694, 4579, 33218, 259483, 2149558, 18672277, 168648090, 1573625606, 15093309024, 148223240022, 1485673163882, 15159644212775, 157142812302992, 1651865171372967, 17582693993265148, 189269329080075275, 2058215511081891400, 22589841589522026553
Offset: 0

Views

Author

N. J. A. Sloane, Mar 19 2015

Keywords

Crossrefs

Representatives for the 16 Wilf-equivalence patterns of length 5 are given in A116485, A047889, and A256195-A256208.
Cf. A099952.

Programs

  • Mathematica
    avoid[n_, pat_] := Module[{p1 = pat[[1]], p2 = pat[[2]], p3 = pat[[3]], p4 = pat[[4]], p5 = pat[[5]], lseq = {}, i, p,
        lpat = Subsets[(n + 1) - Range[n], {Length[pat]}],
        psn = Permutations[Range[n]]},
       For[i = 1, i <= Length[lpat], i++,
        p = lpat[[i]];
        AppendTo[lseq, Select[psn, MemberQ[#, {_, p[[p1]], _, p[[p2]], _, p[[p3]], _, p[[p4]], _, p[[p5]], _}, {0}] &]];
        ]; n! - Length[Union[Flatten[lseq, 1]]]];
    Table[avoid[n, {3, 5, 2, 1, 4}], {n, 0, 8}]  (* Robert Price, Mar 27 2020 *)

Extensions

More terms from Anthony Guttmann, Sep 29 2021

A256198 Number of permutations in S_n that avoid the pattern 35124.

Original entry on oeis.org

1, 1, 2, 6, 24, 119, 694, 4580, 33249, 260092, 2159381, 18815124, 170605392, 1599499163, 15427796984, 152487271455, 1539554179950, 15836801521762, 165625811815111, 1757953168747511, 18908510233855411, 205838673911323648, 2265393020812413370, 25182471016157568626
Offset: 0

Views

Author

N. J. A. Sloane, Mar 19 2015

Keywords

Crossrefs

Representatives for the 16 Wilf-equivalence patterns of length 5 are given in A116485, A047889, and A256195-A256208.
Cf. A099952.

Programs

  • Mathematica
    avoid[n_, pat_] := Module[{p1 = pat[[1]], p2 = pat[[2]], p3 = pat[[3]], p4 = pat[[4]], p5 = pat[[5]], lseq = {}, i, p,
        lpat = Subsets[(n + 1) - Range[n], {Length[pat]}],
        psn = Permutations[Range[n]]},
       For[i = 1, i <= Length[lpat], i++,
        p = lpat[[i]];
        AppendTo[lseq, Select[psn, MemberQ[#, {_, p[[p1]], _, p[[p2]], _, p[[p3]], _, p[[p4]], _, p[[p5]], _}, {0}] &]];
        ]; n! - Length[Union[Flatten[lseq, 1]]]];
    Table[avoid[n, {3, 5, 1, 2, 4}], {n, 0, 8}]  (* Robert Price, Mar 27 2020 *)

Extensions

More terms from Anthony Guttmann, Sep 29 2021

A256199 Number of permutations in S_n that avoid the pattern 53124.

Original entry on oeis.org

1, 1, 2, 6, 24, 119, 694, 4580, 33252, 260202, 2161837, 18858720, 171285237, 1609282391, 15561356705, 154246419725, 1562151687940, 16121960812335, 169178376076607, 1801800479418116, 19446010522240384, 212394673429250090, 2345064355131025130, 26148064110299271293
Offset: 0

Views

Author

N. J. A. Sloane, Mar 19 2015

Keywords

Crossrefs

Representatives for the 16 Wilf-equivalence patterns of length 5 are given in A116485, A047889, and A256195-A256208.
Cf. A099952.

Programs

  • Mathematica
    avoid[n_, pat_] := Module[{p1 = pat[[1]], p2 = pat[[2]], p3 = pat[[3]], p4 = pat[[4]], p5 = pat[[5]], lseq = {}, i, p,
        lpat = Subsets[(n + 1) - Range[n], {Length[pat]}],
        psn = Permutations[Range[n]]},
       For[i = 1, i <= Length[lpat], i++,
        p = lpat[[i]];
        AppendTo[lseq, Select[psn, MemberQ[#, {_, p[[p1]], _, p[[p2]], _, p[[p3]], _, p[[p4]], _, p[[p5]], _}, {0}] &]];
        ]; n! - Length[Union[Flatten[lseq, 1]]]];
    Table[avoid[n, {5, 3, 1, 2, 4}], {n, 0, 8}]  (* Robert Price, Mar 27 2020 *)

Extensions

More terms from Anthony Guttmann, Sep 29 2021
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