cp's OEIS Frontend

Every possible 3-ball asynchronic site swap of finite period occurs as a subsequence of this sequence. E.g., "51" (three-ball shower) occurs first time at a(65)=5, a(66)=1.

We obtain the sequence by traversing each possible loop of successively larger lengths in 3-ball state graph as depicted in Polster's book, or section 7 of Knutson's Siteswap FAQ (but not limited by throw height), starting from and ending to the ground state 7 (xxx) and by concatenating those sequences in lexicographic order.

One can take any subsequence A084501[i..j] such that A084503(i-1) = A084503(j) = 7 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 first 39 terms, one gets a site swap pattern "333423333424234415225313333334234233441".

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

Also minimum i such that A084505(i) >= n. Tells that the n-th throw (n>=1) in A084501 belongs to the a(n)-th lexicographical solution A084502(a(n)).

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".