A248416 Rectangular array by antidiagonals: for n >= 0, row n gives the positions in the Thue-Morse sequence A010059 at which the first 2^n terms occur.
1, 4, 1, 6, 4, 1, 7, 7, 7, 1, 10, 11, 13, 13, 1, 11, 13, 21, 25, 25, 1, 13, 16, 25, 41, 49, 49, 1, 16, 19, 31, 49, 81, 97, 97, 1, 18, 21, 37, 61, 97, 161, 193, 193, 1, 19, 25, 41, 73, 121, 193, 321, 385, 385, 1, 21, 28, 49, 81, 145, 241, 385, 641, 769, 769, 1, 24, 31, 55, 97, 161, 289, 481, 769, 1281, 1537, 1537, 1
Offset: 1
Examples
Northwest corner, n>=0, k>=1: 1 4 6 7 10 11 13 16 18 19 1 4 7 11 13 16 19 21 25 28 1 7 13 21 25 31 37 41 49 55 1 13 25 41 49 61 73 81 97 109 1 25 49 81 97 121 145 161 193 217 1 49 97 161 193 241 289 321 385 433 1 97 193 321 385 481 577 641 769 865 The Thue-Morse sequence A010059 begins with 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, from which we see that the first 4 terms (=1,0,0,1) occur at positions 1, 7, 13, ..., as indicated for row n=2.
Crossrefs
Programs
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Maple
A010060 := proc(n) local i; add(i, i=convert(n, base, 2)) mod 2 ; end proc: A010059 := proc(n) 1-A010060(n) ; end proc: A248416Off0 := proc(n,k) option remember ; local strtN,binpat,src,thue ; if k = 1 then strtN := 0 ; else strtN := 1+procname(n,k-1) ; end if; binpat := [seq(A010059(i),i=0..n-1)] ; for src from strtN do thue := [seq(A010059(i),i=src..src+nops(binpat)-1)] ; if binpat=thue then return src ; end if; end do: end proc: A248416 := proc(n,k) 1+A248416Off0(2^n,k) ; end proc: for d from 1 to 11 do for k from d to 1 by -1 do printf("%d,",A248416(d-k,k)) ; end do: # R. J. Mathar, Nov 06 2018
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Mathematica
z = 3000; u = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {1, 0}}] &, {0}, 20]; Length[u] t[p_, q_] := t[p, q] = Table[u[[k]], {k, p, q}]; r[n_] := Select[Range[z], t[#, # + 2^(n - 1)] == t[1, 1 + 2^(n - 1)] &] TableForm[Table[r[n], {n, 0, 10}]]
Extensions
Definitions and examples clarified. - R. J. Mathar, Nov 06 2018
Comments