Tomas Rokicki has authored 3 sequences.
A372008
Maximum number of moves to solve "Reverse The List of Integers" game with high value n.
Original entry on oeis.org
0, 0, 0, 0, 0, 14, 26, 74, 86, 126, 106, 130
Offset: 1
For n=6, the worst case is 1,6,3 -> 1,4,2,3 -> 5,2,3 -> 4,1,2,3 -> 4,1,5 -> 4,6 -> 1,3,6 -> 1,3,2,4 -> 1,5,4 -> 6,4 -> 5,1,4 -> 3,2,1,4 -> 3,2,5 -> 3,2,4,1 -> 3,6,1. There is no shorter solution for this list, and no other reversible list requires more than 14 moves. So a(6) = 14.
A308721
Locations of the first occurrence of pair (0,n) in the van Eck sequence (A181391).
Original entry on oeis.org
0, 1, 3, 20, 24, 10, 30, 276, 388, 81, 225, 726, 2935, 1408, 7718, 5624, 5680, 85998, 26706, 546290, 1112929, 702575, 3425417, 10537360, 21301906, 217230900, 108698091, 32381774, 846522986, 851764846, 11692311325, 46163898987
Offset: 0
For a(5)=10, the pair (0,5) first occurs in A181391 at element 10.
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With[{s = Nest[# /. {{Longest[p___], a_, q___, a_} :> {p, a, q, a, Length[{a, q}]}, {a___} :> {a, 0}} &, {}, 10^3]}, TakeWhile[#, # > -1 &] &@ Array[If[Length@ # == 0, -1, #[[1, 1]] - 1 ] &@ SequencePosition[s, {0, #}] &, Max@ s, 0]] (* Michael De Vlieger, Jul 08 2019, after JungHwan Min at A181391 *)
A317188
a(n) = 1 + 2 * (a(n-1) + a(n-4) + a(n-6)) + a(n-7) for n>3, with initial values 0 if n<0, and 1,3,8,18 for n=0..3.
Original entry on oeis.org
1, 3, 8, 18, 39, 85, 189, 422, 942, 2099, 4673, 10400, 23148, 51528, 114709, 255359, 568460, 1265450, 2817015, 6270953, 13959773, 31075874, 69178058, 153997383, 342813793, 763138256, 1698823128, 3781752544, 8418564665, 18740578667, 41718428560, 92869452514
Offset: 0
- Fred Lunnon and Tomas Rokicki, Posting to Math Fun Mailing List, circa Jul 25 2018
- Harvey P. Dale, Table of n, a(n) for n = 0..1000
- Index entries for linear recurrences with constant coefficients, signature (3,-2,0,2,-2,2,-1,-1).
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LinearRecurrence[{3,-2,0,2,-2,2,-1,-1},{1,3,8,18,39,85,189,422},40] (* Harvey P. Dale, Oct 15 2021 *)
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