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

A243752 Number T(n,k) of Dyck paths of semilength n having exactly k (possibly overlapping) occurrences of the consecutive step pattern given by the binary expansion of n, where 1=U=(1,1) and 0=D=(1,-1); triangle T(n,k), n>=0, read by rows.

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 1, 3, 1, 1, 11, 2, 9, 16, 12, 4, 1, 1, 57, 69, 5, 127, 161, 98, 35, 7, 1, 323, 927, 180, 1515, 1997, 1056, 280, 14, 4191, 5539, 3967, 1991, 781, 244, 64, 17, 1, 1, 10455, 25638, 18357, 4115, 220, 1, 20705, 68850, 77685, 34840, 5685, 246, 1
Offset: 0

Views

Author

Alois P. Heinz, Jun 09 2014

Keywords

Examples

			Triangle T(n,k) begins:
: n\k :    0     1     2     3    4    5  ...
+-----+----------------------------------------------------------
:  0  :    1;                                 [row  0 of A131427]
:  1  :    0,    1;                           [row  1 of A131427]
:  2  :    0,    1,    1;                     [row  2 of A090181]
:  3  :    1,    3,    1;                     [row  3 of A001263]
:  4  :    1,   11,    2;                     [row  4 of A091156]
:  5  :    9,   16,   12,    4,   1;          [row  5 of A091869]
:  6  :    1,   57,   69,    5;               [row  6 of A091156]
:  7  :  127,  161,   98,   35,   7,   1;     [row  7 of A092107]
:  8  :  323,  927,  180;                     [row  8 of A091958]
:  9  : 1515, 1997, 1056,  280,  14;          [row  9 of A135306]
: 10  : 4191, 5539, 3967, 1991, 781, 244, ... [row 10 of A094507]
		

Crossrefs

A243412 Number of Dyck paths of semilength n avoiding the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 1, 2, 5, 13, 37, 112, 352, 1136, 3742, 12529, 42513, 145868, 505234, 1764157, 6203370, 21947490, 78072209, 279062937, 1001803617, 3610366030, 13057141261, 47373444827, 172381857939, 628944880851, 2300410562946, 8433110899963, 30980398420830, 114034887644860
Offset: 0

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=0 of A243366.
Column k=45 of A243753.

Formula

Recurrence: (n+1)*(n+2)*(817*n^7 - 24387*n^6 + 285094*n^5 - 1647261*n^4 + 4787137*n^3 - 5628540*n^2 - 1552284*n + 6122952)*a(n) = (n+1)*(1634*n^8 - 47957*n^7 + 542786*n^6 - 2900786*n^5 + 6449435*n^4 + 3292426*n^3 - 41693904*n^2 + 63681552*n - 24491808)*a(n-1) + 3*n*(2451*n^8 - 73161*n^7 + 850153*n^6 - 4796076*n^5 + 12712261*n^4 - 7403931*n^3 - 33886709*n^2 + 64848252*n - 30495792)*a(n-2) - (8170*n^9 - 256125*n^8 + 3222045*n^7 - 20734872*n^6 + 70290303*n^5 - 101053185*n^4 - 62925628*n^3 + 384515340*n^2 - 387509328*n + 86320944)*a(n-3) + 3*(4085*n^9 - 134190*n^8 + 1787518*n^7 - 12351340*n^6 + 46074358*n^5 - 78991732*n^4 - 20763151*n^3 + 311152124*n^2 - 443676900*n + 188645328)*a(n-4) - (8170*n^9 - 280635*n^8 + 3929664*n^7 - 28666521*n^6 + 113672493*n^5 - 215520840*n^4 + 17606573*n^3 + 648300408*n^2 - 951192216*n + 363243312)*a(n-5) + 2*(4085*n^9 - 146445*n^8 + 2159949*n^7 - 16771674*n^6 + 71463813*n^5 - 145058547*n^4 - 9273941*n^3 + 640553178*n^2 - 1114925472*n + 598040712)*a(n-6) + (8170*n^9 - 305145*n^8 + 4669113*n^7 - 37343346*n^6 + 161916525*n^5 - 325736907*n^4 - 55373986*n^3 + 1484026824*n^2 - 2345628420*n + 1080273456)*a(n-7) + (6536*n^9 - 253920*n^8 + 4039503*n^7 - 33528057*n^6 + 150519924*n^5 - 315037869*n^4 - 26105741*n^3 + 1400728128*n^2 - 2351058696*n + 1235710944)*a(n-8) + (n-9)*(6536*n^8 - 204900*n^7 + 2511339*n^6 - 14959584*n^5 + 41778954*n^4 - 25451829*n^3 - 129319352*n^2 + 282520572*n - 168563664)*a(n-9) + 3*(n-10)*(n-9)*(817*n^7 - 18668*n^6 + 155929*n^5 - 559001*n^4 + 589888*n^3 + 1351597*n^2 - 3752130*n + 2343528)*a(n-10). - Vaclav Kotesovec, Jun 05 2014
a(n) ~ c * d^n / n^(3/2), where d = 3.8821590268628506747194368909643384060073824... is the root of the equation d^8 - 2*d^7 - 10*d^6 + 12*d^5 - 5*d^4 - 2*d^3 - 5*d^2 - 8*d - 3 = 0, and c = 0.56162811676670317653498040062091920282038218... . - Vaclav Kotesovec, Jun 05 2014

A243413 Number of Dyck paths of semilength n having exactly 1 occurrence of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 5, 19, 70, 259, 962, 3585, 13399, 50201, 188481, 709001, 2671624, 10082895, 38107919, 144214978, 546413880, 2072553851, 7869081412, 29904874545, 113744129791, 432969825404, 1649313815911, 6287005845873, 23980562901849, 91523321091182, 349497990760012
Offset: 4

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=1 of A243366.

Formula

a(n) ~ c * d^n / sqrt(n), where d = 3.8821590268628506747194368909643384... (same as for A243412) is the root of the equation d^8 - 2*d^7 - 10*d^6 + 12*d^5 - 5*d^4 - 2*d^3 - 5*d^2 - 8*d - 3 = 0, and c = 0.0159763870992602878106411532836296... . - Vaclav Kotesovec, Jun 05 2014

A243414 Number of Dyck paths of semilength n having exactly 2 (possibly overlapping) occurrences of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 7, 34, 149, 627, 2584, 10529, 42606, 171563, 688255, 2752912, 10985005, 43747708, 173937910, 690592594, 2738547328, 10848121023, 42931655341, 169759128539, 670744883641, 2648384384709, 10450336782375, 41212385684767, 162440029038575, 639946101535124
Offset: 6

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=2 of A243366.

Formula

a(n) ~ c * d^n * sqrt(n), where d = 3.8821590268628506747194368909643384... (same as for A243412) is the root of the equation d^8 - 2*d^7 - 10*d^6 + 12*d^5 - 5*d^4 - 2*d^3 - 5*d^2 - 8*d - 3 = 0, and c = 0.000227236615409194082906635273578... . - Vaclav Kotesovec, Jun 05 2014

A243415 Number of Dyck paths of semilength n having exactly 3 (possibly overlapping) occurrences of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 9, 54, 279, 1334, 6092, 27048, 117896, 507173, 2160151, 9128266, 38326830, 160063712, 665442560, 2755685897, 11372798741, 46794914849, 192029181971, 786126469079, 3211253947191, 13091799706905, 53277016211285, 216451122516387, 878040805034630
Offset: 8

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=3 of A243366.

A243416 Number of Dyck paths of semilength n having exactly 4 (possibly overlapping) occurrences of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 11, 79, 474, 2561, 12937, 62524, 293146, 1344602, 6065734, 27007870, 118984043, 519589872, 2252141576, 9699519424, 41541816291, 177048628294, 751293699026, 3175665502731, 13376228005419, 56162636663430, 235124074987923, 981718571224412, 4088916793922566
Offset: 10

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=4 of A243366.

A243417 Number of Dyck paths of semilength n having exactly 5 (possibly overlapping) occurrences of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 13, 109, 748, 4531, 25228, 132515, 667747, 3263146, 15576803, 72995158, 336986263, 1536565549, 6933515253, 31007787862, 137599702886, 606467289880, 2656919897648, 11577389890752, 50204031478108, 216750954307831, 932068704988570, 3993428974519241
Offset: 12

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=5 of A243366.

A243418 Number of Dyck paths of semilength n having exactly 6 (possibly overlapping) occurrences of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 15, 144, 1115, 7509, 45864, 261185, 1412742, 7350116, 37106514, 182907585, 884290974, 4207172844, 19747711113, 91627676418, 420914259695, 1916722429108, 8660949017183, 38866735108620, 173341678278027, 768774806179919, 3392247359157876, 14899045118613987
Offset: 14

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=6 of A243366.

A243419 Number of Dyck paths of semilength n having exactly 7 (possibly overlapping) occurrences of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 17, 184, 1589, 11802, 78666, 484163, 2806039, 15527186, 82851064, 429392845, 2173167944, 10783733773, 52629404231, 253233665755, 1203597734972, 5659518993517, 26361150741197, 121755788054172, 558129404726455, 2541096189931118, 11497990460196322
Offset: 16

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=7 of A243366.

A243420 Number of Dyck paths of semilength n having exactly 8 (possibly overlapping) occurrences of the consecutive steps UDUUDU (with U=(1,1), D=(1,-1)).

Original entry on oeis.org

1, 19, 229, 2184, 17759, 128509, 851831, 5278129, 31020976, 174803309, 952033480, 5042006351, 26087126992, 132340281386, 660143136637, 3245280843311, 15751929981822, 75602686035094, 359256881535197, 1691965976395069, 7904617778358794, 36660673151053000
Offset: 18

Views

Author

Alois P. Heinz, Jun 04 2014

Keywords

Crossrefs

Column k=8 of A243366.
Showing 1-10 of 12 results. Next