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.

A200051 Number of -2..2 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

1, 4, 10, 26, 68, 178, 472, 1276, 3462, 9496, 26024, 71956, 198740, 552814, 1535556, 4290252, 11968194, 33553214, 93917400, 264020106, 741024426, 2087799972, 5872999754, 16577458520, 46720454112, 132081262316, 372843051320
Offset: 1

Views

Author

R. H. Hardin Nov 13 2011

Keywords

Comments

Column 2 of A200057

Examples

			Some solutions for n=6
.-1...-1....0....2....0....0....0....0....0...-2....0....0....1...-1...-2...-2
..1...-2...-1....1....1...-1....1....1...-1....1....2...-2....2....1....1....1
..0....2....0....2...-2....2...-2...-1....1...-1...-2....0...-2....0....0...-1
..2...-2...-1...-2....0...-2....1....0....0....1....0...-1....2....1....1....1
.-2....2....2...-1...-1....1...-2...-2....1....0...-1....2...-2...-1...-2...-1
..0....1....0...-2....2....0....2....2...-1....1....1....1...-1....0....2....2
		

A200052 Number of -3..3 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

1, 6, 22, 78, 288, 1098, 4224, 16432, 64310, 253692, 1003374, 3992358, 15908668, 63684848, 255153798, 1026057576, 4127971346, 16658240722, 67237254862, 272092306164, 1101134446908, 4466186295698, 18113540529096, 73607652658268, 299074725301088, 1217290931946978
Offset: 1

Views

Author

R. H. Hardin, Nov 13 2011

Keywords

Examples

			Some solutions for n=6:
.-1...-2....0...-2...-1....1....0...-2...-1....3...-1....1....0....0...-2....1
.-3....0....2....1....1...-2....3....3...-3....0...-3...-2...-1....3....2...-1
..3...-1...-3...-2...-2....3...-1....1....2....2....3....3....3...-1....0....1
.-1....1....2....2....2...-3....3....3...-1...-3....0...-2....0....1....2...-1
..2...-1...-3....0...-2....1...-3...-3....2....1....3....2....1...-3...-2....1
..0....3....2....1....2....0...-2...-2....1...-3...-2...-2...-3....0....0...-1
		

Crossrefs

Column 3 of A200057.

A200053 Number of -4..4 arrays X (0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

1, 8, 36, 172, 840, 4172, 20978, 106674, 545698, 2811236, 14534258, 75522854, 393338058, 2056376914, 10767639532, 56550307652, 297322835298, 1567022163228, 8265441146830, 43685281805084, 231022736833454, 1223830782531260
Offset: 1

Views

Author

R. H. Hardin, Nov 13 2011

Keywords

Comments

Column 4 of A200057.

Examples

			Some solutions for n=6:
.-2....2...-1...-3...-2....4....0...-1....0....2...-4....2...-1....0....0....1
..2...-3....4....1....2....0....4....3...-2....0....2....4....2....4....2....0
..1....2...-3....0...-1....3...-3...-1....4....2...-1....0...-3...-2...-2....2
..4...-1....0....4....0...-3....3....4...-4...-3....1....1....1....1....1...-4
.-3....1...-2...-3...-3....0...-3...-3....2....1...-2...-4....0...-2...-3....4
.-2...-1....2....1....4...-4...-1...-2....0...-2....4...-3....1...-1....2...-3
		

Crossrefs

Cf. A200057.

Programs

  • Maple
    T:= proc(a,n,s)
       option remember;
       if n = 1 then
          if s = a then 1
          else 0
          fi
       else
         add(procname(-j,n-1,a-s), j=a+1..4)
       fi
    end proc:
    A:= proc(n)  2*add(T(a,n,0),a=-4..4) end proc: A(1):= 1:
    seq(A(n), n=1..30); # Robert Israel, Nov 19 2014

A200054 Number of -5..5 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

1, 10, 56, 324, 1948, 11962, 74338, 466548, 2947742, 18746754, 119701782, 767860824, 4938868628, 31876070432, 206122332340, 1336425077996, 8676994345132, 56457974059982, 367738443114696, 2399500033305708
Offset: 1

Views

Author

R. H. Hardin Nov 13 2011

Keywords

Comments

Column 5 of A200057

Examples

			Some solutions for n=6
.-2...-5....3...-4...-5....0...-4....5...-2....4....0....5...-4...-2...-2....0
.-3....4...-3...-1....4...-3....4...-4...-5...-3....3...-5....0...-3....2....5
..5...-3....4...-5...-1....4...-4....1....2....3...-4....0...-3....2....0....0
.-1....2...-5....4....5...-4....3...-5...-3....0...-1...-3....2....0....4....1
..5....0....3....2...-2....5...-4....4....5....1...-3....2....1....3...-3...-5
.-4....2...-2....4...-1...-2....5...-1....3...-5....5....1....4....0...-1...-1
		

A200055 Number of -6..6 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

1, 12, 78, 546, 3914, 28554, 211242, 1577878, 11867186, 89815404, 682642050, 5211283212, 39897460856, 306446600454, 2358644800468, 18199380449274, 140644480480176, 1089068472750998, 8443172123261506, 65564035662489652
Offset: 1

Views

Author

R. H. Hardin Nov 13 2011

Keywords

Comments

Column 6 of A200057

Examples

			Some solutions for n=6
.-2....0...-3...-1...-3....5...-2....5....2....1...-3....0....4...-6...-1...-5
..4....5...-5...-2....1...-3....5...-5....1....0....0...-1...-3....3....0....1
.-5...-3....4....1...-6....1...-6....2....5....1...-1....1....1...-4...-2...-6
..4...-2....2...-3....6...-1....5...-2...-6...-3....2...-2...-6....3....5....3
.-5...-4....5....6....0....1...-4....1....1....4...-3....3....6....1...-2....1
..4....4...-3...-1....2...-3....2...-1...-3...-3....5...-1...-2....3....0....6
		

A200056 Number of -7..7 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

1, 14, 106, 850, 7074, 59910, 514168, 4453946, 38855488, 341052122, 3006680636, 26619825378, 236386648574, 2105717447626, 18798362729604, 168222072625668, 1507848061916274, 13541292792666004, 121763260320351938
Offset: 1

Views

Author

R. H. Hardin Nov 13 2011

Keywords

Comments

Column 7 of A200057

Examples

			Some solutions for n=6
..1....3....1...-6...-5....4...-1....2...-1...-5....6...-3....0...-6....6....1
..5...-4....3....4...-6....5....4...-4....2....6...-1...-1...-4....7...-3....2
.-2...-1....2...-6....4...-5...-5...-1...-3...-4....1...-5....7...-7....7...-3
..7...-5....5....1...-1....0....0...-2....3....4...-7....5...-5....0...-3....5
.-7....6...-7....0....6...-3...-3....5...-4...-7....4....0....5...-1....0...-7
.-4....1...-4....7....2...-1....5....0....3....6...-3....4...-3....7...-7....2
		

A200058 Number of -n..n arrays x(0..3) of 4 elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

4, 26, 78, 172, 324, 546, 850, 1252, 1764, 2398, 3170, 4092, 5176, 6438, 7890, 9544, 11416, 13518, 15862, 18464, 21336, 24490, 27942, 31704, 35788, 40210, 44982, 50116, 55628, 61530, 67834, 74556, 81708, 89302, 97354, 105876, 114880, 124382, 134394
Offset: 1

Views

Author

R. H. Hardin, Nov 13 2011

Keywords

Comments

Row 4 of A200057.

Examples

			Some solutions for n=6:
..2....6...-2....5....6...-2....2...-3....5....2....1....0....3....2....1....6
..5...-6...-3...-2...-4...-3...-4...-4...-5....0....3...-5...-3...-1...-4...-3
.-5....3....5....1....1....3....6....6....6....1...-3....5....1....0....5....0
.-2...-3....0...-4...-3....2...-4....1...-6...-3...-1....0...-1...-1...-2...-3
		

Crossrefs

Cf. A200057.

Formula

Empirical: a(n) = 3*a(n-1) -3*a(n-2) +2*a(n-3) -3*a(n-4) +3*a(n-5) -a(n-6).
Empirical g.f.: 2*x*(2 + x + x^2)*(1 + 3*x + x^2) / ((1 - x)^4*(1 + x + x^2)). - Colin Barker, May 17 2018

A200059 Number of -n..n arrays x(0..4) of 5 elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

6, 68, 288, 840, 1948, 3914, 7074, 11862, 18732, 28244, 40970, 57598, 78816, 105444, 138284, 178282, 226362, 283598, 351026, 429852, 521230, 626492, 746910, 883944, 1038982, 1213616, 1409348, 1627896, 1870884, 2140158, 2437454, 2764750, 3123900
Offset: 1

Views

Author

R. H. Hardin, Nov 13 2011

Keywords

Comments

Row 5 of A200057.

Examples

			Some solutions for n=6:
..1...-1....3...-6...-4...-1....1....4....6...-3....5...-1....1....1....1...-2
..0....2...-6....2....3...-5....2...-6...-1...-5...-6....2...-1....5...-2....6
..1...-2....4...-3...-3....5...-6....3....3....5....6...-4....4...-2....2...-5
.-3....5...-5....4....4...-1....4...-3...-5....1...-4....2...-3...-1...-5....1
..1...-4....4....3....0....2...-1....2...-3....2...-1....1...-1...-3....4....0
		

Crossrefs

Cf. A200057.

Formula

Empirical: a(n) = 2*a(n-1) -a(n-3) -2*a(n-5) +2*a(n-6) +a(n-8) -2*a(n-10) +a(n-11).
Empirical g.f.: 2*x*(3 + 28*x + 76*x^2 + 135*x^3 + 168*x^4 + 159*x^5 + 105*x^6 + 51*x^7 + 10*x^8 + x^9) / ((1 - x)^5*(1 + x)^2*(1 + x^2)*(1 + x + x^2)). - Colin Barker, May 17 2018

A200060 Number of -n..n arrays x(0..5) of 6 elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

10, 178, 1098, 4172, 11962, 28554, 59910, 114232, 202314, 337902, 538054, 823496, 1218978, 1753638, 2461350, 3381092, 4557298, 6040218, 7886274, 10158420, 12926498, 16267598, 20266414, 25015604, 30616142, 37177686, 44818926, 53667948
Offset: 1

Views

Author

R. H. Hardin, Nov 13 2011

Keywords

Comments

Row 6 of A200057.

Examples

			Some solutions for n=6:
..3...-3...-2....4....4...-2...-5....0....1....1....2....1....1...-2...-3...-1
..5...-2...-3....3....5...-6....3....2...-6...-2....5...-6...-2....3....2....6
.-5...-4....3....5...-4....6....2...-3....0....5...-1....1....6...-2....1...-3
.-3....3...-5...-6...-2....0....5....4...-4...-6....2...-2...-6....2....3....0
.-6....1....5...-2...-5....6...-3...-6....6....6...-5....6....1...-3...-6...-2
..6....5....2...-4....2...-4...-2....3....3...-4...-3....0....0....2....3....0
		

Crossrefs

Cf. A200057.

Formula

Empirical: a(n) = 3*a(n-1) -2*a(n-2) -a(n-3) +2*a(n-5) -a(n-6) -a(n-7) +2*a(n-8) -a(n-10) -2*a(n-11) +3*a(n-12) -a(n-13).
Empirical g.f.: 2*x*(5 + 74*x + 292*x^2 + 622*x^3 + 910*x^4 + 1045*x^5 + 999*x^6 + 782*x^7 + 452*x^8 + 162*x^9 + 24*x^10 + x^11) / ((1 - x)^6*(1 + x)*(1 + x + x^2)*(1 + x + x^2 + x^3 + x^4)). - Colin Barker, May 17 2018

A200061 Number of -n..n arrays x(0..6) of 7 elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Original entry on oeis.org

14, 472, 4224, 20978, 74338, 211242, 514168, 1115572, 2215290, 4099888, 7165376, 11941380, 19119208, 29580842, 44432366, 65037696, 93057524, 130487666, 179703518, 243503094, 325156994, 428455996, 557766736, 718083722, 915090720
Offset: 1

Views

Author

R. H. Hardin Nov 13 2011

Keywords

Comments

Row 7 of A200057

Examples

			Some solutions for n=6
..1....4....3...-2....3....6...-3....0...-6...-6...-3....0....4....0...-4....4
.-6....2...-1....0...-6...-6....2....2....6...-4....0...-1....3....4...-6...-6
..6....4....3...-3....2...-2...-4...-4...-4...-5...-6....0....5...-4....6....5
.-6...-6...-1....0...-3...-3....6....6....4....5....5...-3...-6....3....1...-4
..3....0....0...-1....4....6...-5...-5....0....3...-3....5...-4...-6....6....4
..0...-5...-4....6...-6...-3....5....6....1....5....5...-2...-6....4...-4...-5
..2....1....0....0....6....2...-1...-5...-1....2....2....1....4...-1....1....2
		

Formula

Empirical: a(n) = 2*a(n-1) -a(n-3) -a(n-5) +a(n-6) -2*a(n-7) +2*a(n-8) +a(n-9) -a(n-13) -2*a(n-14) +2*a(n-15) -a(n-16) +a(n-17) +a(n-19) -2*a(n-21) +a(n-22)
Showing 1-10 of 10 results.