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A138056 Levels of substitution A103684 (based on the morphism f: 1->{1,2}, 2->{1,3}, 3->{3}) like Markov substitution taken as polynomials p(x,n)]and coefficients of the differential polynomials returned as q(x,n) =dp(x,n)dx coefficients. ( first zero omitted). 0
2, 2, 2, 9, 2, 2, 9, 4, 10, 6, 2, 2, 9, 4, 10, 6, 7, 16, 9, 30, 11, 24, 2, 2, 9, 4, 10, 6, 7, 16, 9, 30, 11, 24, 13, 28, 15, 48, 17, 36, 19, 20, 42, 22, 69, 2, 2, 9, 4, 10, 6, 7, 16, 9, 30, 11, 24, 13, 28, 15, 48, 17, 36, 19, 20, 42, 22, 69, 24, 50, 26, 81, 28, 58, 30, 31, 64, 33, 102, 35 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row sums with zero: {0, 2, 13, 33, 130, 459, 1533, 5266, 17884, 60532, 205129, ...};

This sequence uses the Markov substitution form that I have been using in my chord-geometry/ graph sequences.

This method of differentiating a substitution appears to be new.

LINKS

Table of n, a(n) for n=1..80.

FORMULA

f: 1->{1,2}, 2->{1,3}, 3->{3}); p(x,n)=Sum[Substitution[n,m]*t(m-1),{m,1,n}]; q(x,n)=dp(x,n)dx; out_n,m=Coefficients(q(x,n).

EXAMPLE

{2},

{2, 2, 9},

{2, 2, 9, 4, 10, 6},

{2, 2, 9, 4, 10, 6, 7, 16, 9, 30, 11, 24},

{2, 2, 9, 4, 10, 6, 7, 16, 9, 30, 11, 24, 13, 28, 15, 48, 17, 36, 19, 20, 42, 22, 69},

{2, 2, 9, 4, 10, 6, 7, 16, 9, 30, 11, 24, 13, 28, 15, 48, 17, 36, 19, 20, 42, 22, 69, 24, 50, 26, 81, 28, 58, 30, 31, 64, 33, 102, 35, 72, 37, 76, 39, 120, 41, 84, 43}

MATHEMATICA

Clear[a, s, p, t, m, n]; (* substitution *); s[1] = {1, 2}; s[2] = {1, 3}; s[3] = {1}; t[a_] := Flatten[s /@ a]; p[0] = {1}; p[1] = t[p[0]]; p[n_] := t[p[n - 1]]; (*A103684*); a = Table[p[n], {n, 0, 10}]; Flatten[a]; b = Table[CoefficientList[D[Apply[Plus, Table[a[[n]][[m]]*x^( m - 1), {m, 1, Length[a[[n]]]}]], x], x], {n, 1, 11}]; Flatten[b] Table[Apply[Plus, CoefficientList[D[Apply[Plus, Table[a[[n]][[m]]* x^(m - 1), {m, 1, Length[a[[n]]]}]], x], x]], {n, 1, 11}];

CROSSREFS

Cf. A103684.

Sequence in context: A298647 A068718 A075097 * A340080 A022459 A060804

Adjacent sequences:  A138053 A138054 A138055 * A138057 A138058 A138059

KEYWORD

nonn,uned,tabf

AUTHOR

Roger L. Bagula, May 02 2008

STATUS

approved

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Last modified December 3 02:44 EST 2021. Contains 349445 sequences. (Running on oeis4.)