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 1-6 of 6 results.

A084518 Partial sums of A084519. Positions of ones in the first differences of A084516.

Original entry on oeis.org

1, 2, 5, 18, 65, 238, 877, 3234, 11929, 44006, 162341, 598890, 2209361, 8150542, 30068125, 110924178, 409209865, 1509614198, 5569110677, 20544980154, 75792390209, 279605352286, 1031490797581, 3805267877730, 14037995932921
Offset: 1

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Author

Antti Karttunen, Jun 02 2003

Keywords

Programs

  • Mathematica
    Accumulate[LinearRecurrence[{3,2,2},{1,1,3},30]] (* Harvey P. Dale, Jul 20 2013 *)

Formula

Empirical G.f.: x*(1-2*x-2*x^2)/((1-x)*(1-3*x-2*x^2-2*x^3)). [Colin Barker, Apr 17 2012]

A084511 An infinite juggling sequence of three balls: successively larger indecomposable ground-state 3-ball site swaps listed in lexicographical order. A subset of A084501.

Original entry on oeis.org

3, 4, 2, 4, 4, 1, 5, 2, 2, 5, 3, 1, 4, 4, 4, 0, 4, 5, 1, 2, 4, 5, 3, 0, 5, 2, 4, 1, 5, 3, 4, 0, 5, 5, 1, 1, 5, 5, 2, 0, 6, 2, 2, 2, 6, 2, 3, 1, 6, 3, 1, 2, 6, 3, 3, 0, 6, 4, 1, 1, 6, 4, 2, 0, 4, 4, 5, 0, 2, 4, 5, 1, 4, 1, 4, 5, 5, 0, 1, 4, 6, 1, 2, 2, 4, 6, 1, 3, 1, 4, 6, 3, 0, 2, 4, 6, 4, 0, 1, 5, 2, 4, 4, 0, 5
Offset: 1

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Author

Antti Karttunen, Jun 02 2003

Keywords

Comments

By "indecomposable" we mean that the juggling state sequence associated to each loop should not return to the ground state 7 (xxx) until after the last throw. I.e., this means that A084515 gives positions of ALL the 7s (ground states) in A084513.
One can take any subsequence A084511[A084515(i)+1..A084515(j)] (j>i) and try to juggle it periodically or give it to one of the Siteswap animators available at J.I.S., e.g., by taking the terms 4-12, one gets a site swap pattern "441522531".

Examples

			The successive site swaps are: 3; 4,2; 4,4,1; 5,2,2; 5,3,1; 4,4,4,0; 4,5,1,2; 4,5,3,0; ... See A084512.
		

Crossrefs

Subset: A084521.
The number of such site swaps of length n is given by A084519.
First position where n appears: A084517.

A084509 Number of ground-state 3-ball juggling sequences of period n.

Original entry on oeis.org

1, 1, 2, 6, 24, 96, 384, 1536, 6144, 24576, 98304, 393216, 1572864, 6291456, 25165824, 100663296, 402653184, 1610612736, 6442450944, 25769803776, 103079215104, 412316860416, 1649267441664, 6597069766656, 26388279066624, 105553116266496, 422212465065984
Offset: 0

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Author

Antti Karttunen, Jun 02 2003

Keywords

Comments

This sequence counts the length n asynchronic site swaps given in A084501/A084502.
Equals row sums of triangle A145463. - Gary W. Adamson, Oct 11 2008
a(n) is the number of permutations of length n+1 avoiding the partially ordered pattern (POP) {1>2, 1>3, 1>4, 1>5} of length 5. That is, the number of length n+1 permutations having no subsequences of length 5 in which the first element is the largest. - Sergey Kitaev, Dec 11 2020
a(n) is the number of permutations p[1]..p[n] of {1,...,n} with p[j+1] < p[j]+4 for 0 < j < n. - Don Knuth, Apr 25 2022

References

  • B. Polster, The Mathematics of Juggling, Springer-Verlag, 2003, p. 48.

Crossrefs

First differences of A084508.
INVERT transform of A084519.

Programs

  • Maple
    A084509 := n -> `if`((n<4),n!,6*(4^(n-3)));
    INVERT([seq(A084519(n),n=1..12)]);
  • Mathematica
    LinearRecurrence[{4},{1,2,6},30] (* Harvey P. Dale, Aug 23 2018 *)

Formula

a(n) = n! for n <= 4, a(n) = 6*4^(n-3) = A002023(n-3) for n >= 3.
G.f.: 1 + x*(1 - 2*x - 2*x^2)/(1 - 4*x). - Philippe Deléham, Aug 16 2005

Extensions

a(0)=1 prepended by Alois P. Heinz, Dec 11 2020

A084512 Successively larger 3-ball indecomposable ground-state site swaps of A084511 in concatenated decimal notation.

Original entry on oeis.org

3, 42, 441, 522, 531, 4440, 4512, 4530, 5241, 5340, 5511, 5520, 6222, 6231, 6312, 6330, 6411, 6420, 44502, 45141, 45501, 46122, 46131, 46302, 46401, 52440, 52512, 52530, 53502, 55140, 55500, 56112, 56130, 56202, 56400, 62241, 62340, 62511
Offset: 1

Views

Author

Antti Karttunen, Jun 02 2003

Keywords

Comments

Note that this decimal representation works only up to the A084510(A084517(10))-1 = 2748th term which is 99600000, after which follows the 2749th solution 10,2,2,2,2,2,2,2 which would be usually represented as "A2222222".

Crossrefs

The number of terms of length n is given by A084519.
Subset of A084502. Cf. A084522.

A084529 Number of 'prime' ground-state 3-ball juggling sequences of period n.

Original entry on oeis.org

1, 1, 3, 12, 42, 142, 502, 1702, 5878
Offset: 1

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Author

Antti Karttunen, Jun 02 2003

Keywords

Comments

This sequence counts the length n asynchronic site swaps given in A084521/A084522.
A juggling sequence is defined as 'prime', if it does not visit any state more than once. This means that in A084523 no integer occurs twice between consecutive sevens.

References

  • B. Polster, The Mathematics of Juggling, Springer-Verlag, 2003, pp. 50-51.

Crossrefs

First differences of A084528. Cf. A084509, A084519.

A145463 Eigentriangle, row sums = A084509.

Original entry on oeis.org

1, 1, 1, 3, 1, 2, 13, 3, 2, 6, 47, 13, 6, 6, 24, 173, 47, 26, 18, 24, 96, 639, 173, 94, 78, 72, 96, 384, 2357, 639, 346, 282, 312, 288, 384, 1536, 8695, 2357, 1278, 1038, 1128, 1248, 1152, 1536, 6144, 32077, 8695, 4714, 3834, 4152, 4512, 4992, 4608, 6144, 24576
Offset: 1

Views

Author

Gary W. Adamson, Oct 11 2008

Keywords

Comments

Row sums = A084509: (1, 2, 6, 24, 96, 384, 1536,...).
Right border = A084509 shifted: (1, 1, 2, 6, 24,...).
Sum of n-th row terms = rightmost term of next row.

Examples

			First few rows of the triangle =
1;
1, 1;
3, 1, 2;
13, 3, 2, 6;
47, 13, 6, 6, 24;
173, 47, 26, 18, 24, 96;
639, 173, 94, 78, 72, 96, 384;
2357, 639, 346, 282, 312, 288, 384, 1536;
...
Row 4 = (13, 3, 2, 6) = termwise products of (13, 3, 1, 1) and (1, 1, 2, 6).
		

Crossrefs

Formula

Triangle read by rows, M * (A084509 * 0^(n-k)). M = an infinite lower triangular matrix with A084519: (1, 1, 3, 13, 47, 173,...) in every column; and (A084509 * 0^(n-k)) = an infinite lower triangular matrix with A084509 (1, 2, 6, 24, 96,...) shifted: (1, 1, 2, 6, 24, 96, 384,...) as the right diagonal and the rest zeros.
Showing 1-6 of 6 results.