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 10 results.

A213114 Number of binary arrays of length n+7 with fewer than 4 ones in any length 8 subsequence (=less than 50% duty cycle).

Original entry on oeis.org

93, 151, 252, 424, 714, 1198, 1996, 3292, 5359, 8758, 14401, 23772, 39313, 65046, 107572, 177700, 293113, 483115, 796360, 1313385, 2167141, 3576909, 5904270, 9745234, 16082476, 26536889, 43783532, 72238736, 119193082, 196678607
Offset: 1

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Author

R. H. Hardin Jun 05 2012

Keywords

Comments

Column 4 of A213118

Examples

			Some solutions for n=3
..1....0....1....0....1....1....1....1....0....1....1....1....0....0....0....0
..0....0....0....1....1....0....1....1....1....0....1....0....0....1....0....0
..0....1....0....0....0....1....1....0....0....0....0....0....1....1....0....1
..1....0....0....0....1....0....0....1....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....1....1....0....0....0....1....0....1
..0....1....1....0....0....0....0....0....1....0....0....0....0....0....0....1
..0....0....0....0....0....1....0....0....0....0....1....0....1....0....1....0
..0....0....1....0....0....0....0....0....0....1....0....0....0....0....1....0
..1....0....0....0....1....0....0....1....0....0....0....1....0....0....0....0
..1....1....1....0....0....1....1....1....1....0....1....0....1....0....0....0
		

Formula

Empirical: a(n) = a(n-1) +a(n-3) +a(n-6) +a(n-7) +7*a(n-8) +a(n-9) -6*a(n-11) -3*a(n-12) -a(n-13) -5*a(n-14) -a(n-15) -21*a(n-16) -13*a(n-17) -5*a(n-18) +14*a(n-19) +9*a(n-20) -a(n-21) +10*a(n-22) +35*a(n-24) +22*a(n-25) +5*a(n-26) -20*a(n-27) -9*a(n-28) -a(n-29) -10*a(n-30) -a(n-31) -35*a(n-32) -13*a(n-33) +15*a(n-35) +3*a(n-36) +5*a(n-38) +a(n-39) +21*a(n-40) +a(n-41) -6*a(n-43) -a(n-46) -7*a(n-48) +a(n-49) +a(n-51) +a(n-56)

A213115 Number of binary arrays of length n+9 with fewer than 5 ones in any length 10 subsequence (=less than 50% duty cycle).

Original entry on oeis.org

386, 646, 1110, 1926, 3354, 5842, 10154, 17578, 30256, 51692, 87508, 148556, 253348, 433455, 743027, 1274970, 2188430, 3755600, 6441345, 11038715, 18900654, 32346074, 55355775, 94759703, 162266073, 277937560, 476145196, 815757624
Offset: 1

Views

Author

R. H. Hardin Jun 05 2012

Keywords

Comments

Column 5 of A213118

Examples

			Some solutions for n=3
..1....1....0....0....1....0....0....0....1....1....0....1....1....0....0....1
..0....1....0....1....1....1....0....1....1....0....1....0....0....0....1....0
..0....1....0....0....0....0....0....0....0....0....1....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....1....1....0....0....0....1
..0....0....1....0....0....0....0....0....0....0....0....0....0....1....1....0
..0....1....0....0....0....0....1....1....1....0....0....1....0....0....1....0
..1....0....0....0....1....0....1....0....1....1....1....1....1....0....0....1
..0....0....0....0....0....0....0....0....0....0....0....0....1....0....0....1
..0....0....1....1....1....0....1....0....0....1....0....0....0....1....0....0
..0....0....0....1....0....0....0....1....0....1....0....0....0....1....0....0
..1....1....1....1....1....0....1....1....1....1....0....1....0....1....1....1
..1....1....0....0....0....1....0....1....1....0....0....0....0....0....1....0
		

A213116 Number of binary arrays of length n+11 with fewer than 6 ones in any length 12 subsequence (=less than 50% duty cycle).

Original entry on oeis.org

1586, 2710, 4748, 8404, 14946, 26630, 47448, 84424, 149836, 264980, 466456, 816488, 1419532, 2473160, 4324006, 7580078, 13311610, 23403052, 41170036, 72441344, 127454361, 224172863, 394092240, 692400868, 1215811672, 2134163576
Offset: 1

Views

Author

R. H. Hardin Jun 05 2012

Keywords

Comments

Column 6 of A213118

Examples

			Some solutions for n=3
..1....0....1....0....1....1....0....1....1....0....0....0....0....0....1....1
..0....1....0....0....1....0....1....0....0....0....1....0....1....0....0....1
..0....0....0....0....0....1....0....1....1....0....0....1....0....0....0....0
..0....1....0....0....0....0....0....0....0....0....0....0....1....0....0....0
..1....0....1....1....0....0....0....0....0....0....1....0....1....0....1....0
..0....0....0....0....1....1....0....1....0....0....0....0....1....1....0....1
..0....0....0....1....0....0....1....0....0....0....0....0....0....0....0....0
..1....1....0....1....0....0....1....1....0....0....1....0....0....1....0....0
..0....0....0....0....1....0....0....0....0....1....0....1....0....0....1....0
..0....0....1....0....0....0....0....0....0....1....0....1....0....0....1....1
..1....1....0....1....0....1....1....1....0....0....1....1....1....1....0....1
..1....1....1....0....1....0....1....0....0....1....1....0....0....1....0....0
..1....0....0....0....0....0....0....0....0....1....0....1....0....0....0....0
..0....0....1....1....1....0....1....1....1....0....0....0....1....1....1....1
		

A213117 Number of binary arrays of length n+13 with fewer than 7 ones in any length 14 subsequence (=less than 50% duty cycle).

Original entry on oeis.org

6476, 11236, 19964, 35836, 64664, 116992, 211888, 383728, 694264, 1253960, 2259448, 4058744, 7263712, 12941840, 22939024, 40724900, 72502576, 129361304, 231174484, 413570984, 740406336, 1326075896, 2375408640, 4254942768
Offset: 1

Views

Author

R. H. Hardin Jun 05 2012

Keywords

Comments

Column 7 of A213118

Examples

			Some solutions for n=3
..1....1....1....0....0....1....1....1....1....1....1....1....1....0....1....0
..1....0....0....1....1....0....0....1....1....1....0....0....1....0....0....1
..0....0....1....1....0....1....1....0....0....0....0....0....0....1....0....0
..0....0....0....1....0....0....1....0....0....0....1....0....0....0....1....0
..1....1....0....0....0....0....0....1....1....0....1....0....1....0....1....1
..0....0....0....1....1....1....0....0....1....0....0....1....1....1....0....0
..1....1....1....0....0....0....0....0....0....0....0....1....1....0....0....0
..0....1....1....0....1....1....1....0....0....1....0....1....1....0....1....1
..0....1....1....0....0....0....1....0....0....1....0....0....0....0....1....1
..1....1....1....0....1....0....0....0....1....0....1....0....0....1....1....0
..0....0....0....1....0....1....0....1....0....0....1....0....0....0....0....1
..0....0....0....0....1....0....1....1....0....1....0....0....0....0....0....0
..1....0....0....0....0....1....0....0....0....0....0....1....0....1....0....0
..0....0....0....1....1....0....0....0....0....0....1....0....0....1....0....0
..1....1....1....0....0....0....1....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....1....0....1....1....0....0....0....1....1....0....1
		

A213119 Number of binary arrays of length 2*n+1 with fewer than n ones in any length 2n subsequence (=less than 50% duty cycle).

Original entry on oeis.org

1, 7, 34, 151, 646, 2710, 11236, 46231, 189214, 771442, 3136156, 12720982, 51507964, 208260556, 841065544, 3393346711, 13679459854, 55106773786, 221860011244, 892741834546, 3590659699444, 14436037598836, 58018598086264
Offset: 1

Views

Author

R. H. Hardin, Jun 05 2012

Keywords

Comments

Row 2 of A213118.

Examples

			Some solutions for n=3
..0....0....1....1....0....1....1....0....1....1....0....0....0....0....0....0
..0....1....0....0....0....0....0....0....0....0....1....0....0....0....0....0
..0....0....0....0....0....0....0....1....0....0....1....1....0....0....1....0
..1....0....0....0....0....0....0....0....1....0....0....1....1....1....0....0
..0....1....1....0....0....0....0....0....0....1....0....0....1....0....0....0
..1....0....0....1....1....0....1....0....0....0....0....0....0....0....0....1
..0....0....0....0....1....1....1....0....0....1....0....0....0....0....1....0
		

Programs

  • Mathematica
    Table[4^n-3*Binomial[2*n-1,n],{n,1,20}] (* Vaclav Kotesovec, Oct 29 2012 *)

Formula

Recurrence: n*a(n) = 2*(4*n-3)*a(n-1) - 8*(2*n-3)*a(n-2). - Vaclav Kotesovec, Oct 19 2012
G.f.: 1/(1-4*x)-3/(2*sqrt(1-4*x)). - Vaclav Kotesovec, Oct 21 2012
a(n) = 4^n - 3*C(2*n-1,n). - Vaclav Kotesovec, Oct 29 2012

A213120 Number of binary arrays of length 2*n+2 with fewer than n ones in any length 2n subsequence (=less than 50% duty cycle).

Original entry on oeis.org

1, 10, 54, 252, 1110, 4748, 19964, 83024, 342678, 1406748, 5751636, 23443240, 95319484, 386805112, 1567130168, 6340730552, 25626393878, 103472018492, 417449893988, 1682982404072, 6780908053268, 27306234108392, 109907864408648
Offset: 1

Views

Author

R. H. Hardin Jun 05 2012

Keywords

Comments

Row 3 of A213118.

Examples

			Some solutions for n=3
..0....0....0....0....1....1....0....0....0....0....0....0....0....1....0....1
..0....1....0....0....0....0....0....1....0....0....0....0....1....1....0....0
..0....1....1....0....1....1....0....0....0....0....0....1....0....0....1....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....1....1....0....0....0....1....0....0....0....1
..1....0....1....0....0....0....0....0....0....1....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....1....1....0....0....1....0....0....1
..0....1....0....0....0....1....1....0....0....0....1....0....1....1....1....0
		

Programs

  • Mathematica
    Table[2^(2*n+1)-(15*n-8)*Binomial[2*n-2,n-1]/n,{n,1,20}] (* Vaclav Kotesovec, Oct 29 2012 *)

Formula

Recurrence: n*(5*n-13)*a(n) = 2*(20*n^2-67*n+40)*a(n-1) - 8*(2*n-5)*(5*n-8) * a(n-2). - Vaclav Kotesovec, Oct 19 2012
a(n) = 2^(2*n+1) - (15*n-8)*C(2*n-2,n-1)/n. - Vaclav Kotesovec, Oct 29 2012

A213121 Number of binary arrays of length 2*n+3 with fewer than n ones in any length 2n subsequence (=less than 50% duty cycle).

Original entry on oeis.org

1, 14, 86, 424, 1926, 8404, 35836, 150604, 626726, 2589844, 10646676, 43594464, 177950236, 724578824, 2944375096, 11944652884, 48388816486, 195794585044, 791434666276, 3196307541904, 12898839944116, 52019043912664
Offset: 1

Views

Author

R. H. Hardin, Jun 05 2012

Keywords

Comments

Row 4 of A213118.

Examples

			Some solutions for n=3
..0....0....1....0....0....0....0....0....0....0....1....1....1....1....0....1
..0....0....0....0....0....1....0....1....1....0....1....0....0....0....0....0
..1....1....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....1....0....0....0....1....0....1....0....0....0....0....0....1
..1....0....1....0....1....1....0....0....1....1....0....0....0....0....0....0
..0....0....0....0....1....0....0....0....0....0....0....0....1....0....0....0
..0....0....0....0....0....0....0....0....0....0....1....0....0....1....0....0
..0....1....0....1....0....0....0....0....0....0....0....1....1....0....1....0
..0....1....1....0....0....1....0....0....0....0....0....1....0....0....1....0
		

Programs

  • Mathematica
    Table[2^(2*n+2)-5*(7*n-4)*Binomial[2*n-2,n-1]/n,{n,1,20}] (* Vaclav Kotesovec, Oct 29 2012 *)

Formula

Recurrence: n*(7*n-19)*a(n) = 2*(28*n^2-97*n+60)*a(n-1) - 8*(2*n-5)*(7*n-12) * a(n-2). - Vaclav Kotesovec, Oct 19 2012
a(n) = 2^(2*n+2) - 5*(7*n-4)*C(2*n-2,n-1)/n. - Vaclav Kotesovec, Oct 29 2012

A213122 Number of binary arrays of length 2*n+4 with fewer than n ones in any length 2n subsequence (=less than 50% duty cycle).

Original entry on oeis.org

1, 19, 136, 714, 3354, 14946, 64664, 274676, 1152494, 4793874, 19813536, 81495084, 333932596, 1364199604, 5559496912, 22610923448, 91805888342, 372224952818, 1507347830672, 6097720950428, 24644919356012, 99527343620348
Offset: 1

Views

Author

R. H. Hardin Jun 05 2012

Keywords

Comments

Row 5 of A213118

Examples

			Some solutions for n=3
..0....0....0....0....0....0....0....0....1....1....1....0....0....0....1....1
..1....0....1....0....0....0....1....0....0....0....0....0....0....1....0....0
..0....0....0....0....0....0....0....1....0....1....0....0....1....0....1....0
..0....0....0....0....0....0....0....0....1....0....0....1....0....0....0....0
..1....0....0....0....1....0....1....0....0....0....0....0....0....0....0....0
..0....1....0....0....1....0....0....1....0....0....0....0....0....0....0....0
..0....0....0....1....0....1....0....0....0....1....0....0....0....1....0....0
..1....0....0....1....0....0....0....0....0....0....1....1....1....0....1....1
..0....0....1....0....0....1....0....1....0....1....0....0....0....0....0....0
..0....1....0....0....0....0....1....0....1....0....1....0....1....1....0....0
		

Formula

Empirical: 3*n*(77*n-237)*a(n) = 2*(924*n^2-3545*n+2311)*a(n-1) - 8*(462*n^2-2131*n+2347)*a(n-2) - 128*(2*n-9)*a(n-3). - Vaclav Kotesovec, Oct 19 2012

A213123 Number of binary arrays of length 2*n+5 with fewer than n ones in any length 2n subsequence (=less than 50% duty cycle).

Original entry on oeis.org

1, 26, 212, 1198, 5842, 26630, 116992, 502492, 2126238, 8903350, 36998056, 152862180, 628749892, 2576996188, 10531805664, 42940549576, 174734720374, 709858318486, 2879728611544, 11668224303796, 47228199967804
Offset: 1

Views

Author

R. H. Hardin, Jun 05 2012

Keywords

Examples

			Some solutions for n=3:
  0  1  1  0  0  1  1  0  0  0  1  0  1  0  1  0
  1  0  0  0  1  0  0  0  1  1  0  0  0  0  0  0
  0  1  0  1  1  0  0  0  0  1  1  0  0  0  0  0
  0  0  0  0  0  0  0  0  1  0  0  1  0  0  0  0
  0  0  0  0  0  1  0  0  0  0  0  0  0  0  0  0
  0  0  1  0  0  0  0  0  0  0  0  0  0  1  0  0
  1  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0
  0  1  1  0  0  1  1  0  0  1  1  0  0  1  1  0
  0  1  0  1  0  0  0  1  1  0  0  0  0  0  0  0
  0  0  0  0  1  0  1  0  0  0  0  0  0  0  0  1
  0  0  0  0  0  0  0  0  1  1  0  0  1  0  0  0
		

Crossrefs

Row 6 of A213118.

Programs

  • Maple
    #verified first terms (holds for all n<=210).
    with(gfun): A213123:= rectoproc({a(3)=212, a(4)=1198, n*(33*n^2-213*n+340)*a(n) = 2*(132*n^3-951*n^2+2029*n-1120)*a(n-1) - 8*(2*n-7)*(33*n^2-147*n+160)*a(n-2)},a(n),remember): 1,26,seq(A213123(n),n=3..20); A213123(210); # Vaclav Kotesovec, Nov 20 2012

Formula

Empirical (for n>=5): n*(33*n^2 - 213*n + 340)*a(n) = 2*(132*n^3 - 951*n^2 + 2029*n - 1120)*a(n-1) - 8*(2*n-7)*(33*n^2 - 147*n + 160)*a(n-2). - Vaclav Kotesovec, Nov 20 2012
Empirical (for n>=3): a(n) = 4^(n+2) - 42*(33*n^2 - 71*n + 32) * C(2*n - 5, n - 3) / ((n-1)*n). - Vaclav Kotesovec, Nov 20 2012

A213124 Number of binary arrays of length 2*n+6 with fewer than n ones in any length 2n subsequence (=less than 50% duty cycle).

Original entry on oeis.org

1, 36, 324, 1996, 10154, 47448, 211888, 920744, 3930286, 16570608, 69240296, 287379592, 1186575444, 4879222736, 19997163520, 81735122832, 333327346838, 1356783786272, 5513802056888, 22376476701512, 90701190829388
Offset: 1

Views

Author

R. H. Hardin, Jun 05 2012

Keywords

Examples

			Some solutions for n=3:
  1  0  0  1  0  1  1  0  0  0  0  0  0  0  1  0
  0  1  1  1  0  0  0  0  0  0  1  1  0  1  0  0
  0  1  1  0  0  0  0  0  0  0  0  1  1  1  0  0
  0  0  0  0  1  0  0  1  1  1  1  0  1  0  0  0
  0  0  0  0  1  0  0  0  0  0  0  0  0  0  0  0
  1  0  0  0  0  0  1  0  0  0  0  0  0  0  0  0
  0  0  0  0  0  1  0  0  0  0  0  0  0  0  1  1
  1  0  0  0  0  0  0  1  0  0  0  0  0  1  0  1
  0  0  1  0  0  0  0  0  0  0  0  1  1  1  1  0
  0  1  0  1  1  0  0  0  1  0  1  1  0  0  0  0
  0  0  1  1  0  0  0  0  0  1  0  0  0  0  0  0
  1  0  0  0  0  1  0  1  1  1  1  0  0  0  0  0
		

Crossrefs

Row 7 of A213118.

Programs

  • Maple
    #verified first terms (holds for all n<=210). - Vaclav Kotesovec, Nov 20 2012
    with(gfun): A213124:= rectoproc({a(3)=324, a(4)=1996, n*(143*n^3-1584*n^2+5761*n-6880)*a(n) = 2*(572*n^4-6765*n^3+27961*n^2-46078*n+23040)*a(n-1) - 8*(2*n-9)*(143*n^3-1155*n^2+3022*n-2560)*a(n-2)},a(n),remember): 1,36,seq(A213124(n),n=3..20); A213124(210);

Formula

Empirical (for n>=5): n*(143*n^3 - 1584*n^2 + 5761*n - 6880)*a(n) = 2*(572*n^4 - 6765*n^3 + 27961*n^2 - 46078*n + 23040)*a(n-1) - 8*(2*n-9)*(143*n^3 - 1155*n^2 + 3022*n - 2560)*a(n-2). - Vaclav Kotesovec, Nov 20 2012
Empirical (for n>=4): a(n) = 2^(2*n+5) - 12*(1001*n^3 - 4697*n^2 + 6510*n - 2560) * C(2*n-7, n-4) / ((n-2)*(n-1)*n). - Vaclav Kotesovec, Nov 20 2012
Showing 1-10 of 10 results.