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A271486
Maximal term of TRIP-Stern sequence of level n corresponding to permutation triple (e,13,23).
8
1, 2, 3, 4, 6, 8, 11, 16, 22, 30, 43, 60, 82, 113, 162, 224, 306, 435, 610, 836, 1168, 1637, 2282, 3120, 4399, 6131, 8522, 11812, 16561, 22933, 31810, 44468, 62335, 85639, 119452, 167281, 233169, 320747, 449700, 626513, 872175
OFFSET
0,2
LINKS
Ilya Amburg, Krishna Dasaratha, Laure Flapan, Thomas Garrity, Chansoo Lee, Cornelia Mihaila, Nicholas Neumann-Chun, Sarah Peluse, Matthew Stoffregen, Stern Sequences for a Family of Multidimensional Continued Fractions: TRIP-Stern Sequences, arXiv:1509.05239 [math.CO], 2015.
MAPLE
A271486T := proc(n)
option remember;
local an ;
if n = 1 then
[1, 1, 1] ;
else
an := procname(floor(n/2)) ;
if type(n, 'even') then
# apply F0
[op(1, an)+op(3, an), op(3, an), op(2, an)] ;
else
# apply F1
[op(1, an), op(1, an)+op(3, an), op(2, an)] ;
end if;
end if;
end proc:
A271486 := proc(n)
local a, l, nmax;
a := 0 ;
for l from 2^n to 2^(n+1)-1 do
nmax := max( op(A271486T(l)) );
a := max(a, nmax) ;
end do:
a ;
end proc: # R. J. Mathar, Apr 16 2016
MATHEMATICA
A271487T[n_] := A271487T[n] = Module[{an}, If[n == 1, {1, 1, 1}, an = A271487T[Floor[n/2]]; If[EvenQ[n], {an[[1]] + an[[3]], an[[3]], an[[2]]}, {an[[1]], an[[1]] + an[[3]], an[[2]]}]]];
a[n_] := a[n] = Module[{a = 0, l, nMax}, For[l = 2^n, l <= 2^(n + 1) - 1, l++, nMax = Max[A271487T[l]]; a = Max[a, nMax]]; a];
Table[Print["a(", n, ") = ", a[n]]; a[n], {n, 0, 19}] (* Jean-François Alcover, Nov 17 2017, after R. J. Mathar *)
CROSSREFS
For sequences mentioned in Conjecture 5.8 of Amburg et al. (2015) see A271485, A000930, A271486, A271487, A271488, A164001, A000045, A271489.
Sequence in context: A321359 A321567 A066806 * A226187 A294922 A317669
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Apr 13 2016
EXTENSIONS
a(20)-a(40) from Lars Blomberg, Jan 08 2018
STATUS
approved