A097181
Triangle read by rows in which row n gives coefficients of polynomial R_n(y) that satisfies R_n(1/2) = 8^n, where R_n(y) forms the initial (n+1) terms of g.f. A097182(y)^(n+1).
Original entry on oeis.org
1, 1, 14, 1, 21, 210, 1, 28, 378, 3220, 1, 35, 595, 6475, 49910, 1, 42, 861, 11396, 108402, 778596, 1, 49, 1176, 18326, 207074, 1791930, 12198004, 1, 56, 1540, 27608, 361018, 3647672, 29389492, 191682920, 1, 63, 1953, 39585, 587727, 6783147
Offset: 0
Row polynomials evaluated at y=1/2 equals powers of 8:
8^1 = 1 + 14/2;
8^2 = 1 + 21/2 + 210/2^2;
8^3 = 1 + 28/2 + 378/2^2 + 3220/2^3;
8^4 = 1 + 35/2 + 595/2^2 + 6475/2^3 + 49910/2^4;
where A097182(y)^(n+1) has the same initial terms as the n-th row:
A097182(y) = 1 + 7*x + 21*x^2 + 21*x^3 - 63*x^4 - 231*x^5 -+...
A097182(y)^2 = 1 + 14y +...
A097182(y)^3 = 1 + 21y + 210y^2 +...
A097182(y)^4 = 1 + 28y + 378y^2 + 3220y^3 +...
A097182(y)^5 = 1 + 35y + 595y^2 + 6475y^3 + 49910y^4 +...
Rows begin with n=0:
1;
1, 14;
1, 21, 210;
1, 28, 378, 3220;
1, 35, 595, 6475, 49910;
1, 42, 861, 11396, 108402, 778596;
1, 49, 1176, 18326, 207074, 1791930, 12198004;
1, 56, 1540, 27608, 361018, 3647672, 29389492, 191682920;
1, 63, 1953, 39585, 587727, 6783147, 62974371, 479497491, 3019005990; ...
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Table[SeriesCoefficient[2*y/((1-16*x*y) + (2*y-1)*(1-16*x*y)^(7/8)), {x, 0,n}, {y,0,k}], {n,0,10}, {k,0,n}]//Flatten (* G. C. Greubel, Sep 17 2019 *)
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{T(n,k)=if(n==0,1,if(k==0,1,if(k==n, 2^n*(4^n -sum(j=0,n-1, T(n,j)/2^j)), polcoeff((Ser(vector(n,i,T(n-1,i-1)),x) +x*O(x^k))^((n+1)/n),k,x))))}
A097184
G.f. A(x) satisfies A097182(x*A(x)) = A(x) and so equals the ratio of the g.f.s of any two adjacent diagonals of triangle A097181.
Original entry on oeis.org
1, 7, 70, 805, 9982, 129766, 1742572, 23960365, 335445110, 4763320562, 68418604436, 992069764322, 14499481170860, 213349508656940, 3157572728122712, 46968894330825341, 701770538825272742, 10526558082379091130, 158452400608443161220
Offset: 0
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R:=PowerSeriesRing(Rationals(), 20); Coefficients(R!( (1-(1-16*x)^(1/8))/(2*x) )); // G. C. Greubel, Sep 17 2019
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seq(coeff(series((1-(1-16*x)^(1/8))/(2*x), x, n+2), x, n), n = 0..20); # G. C. Greubel, Sep 17 2019
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CoefficientList[Series[(1-(1-16*x)^(1/8))/(2*x), {x, 0, 20}], x] (* Vaclav Kotesovec, Feb 09 2014 *)
Table[FullSimplify[16^n*Gamma[n+7/8]/(Gamma[7/8]*Gamma[n+2])], {n, 0, 20}] (* Vaclav Kotesovec, Feb 09 2014 *)
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a(n)=polcoeff((1-(1-16*x+x^2*O(x^n))^(1/8))/(2*x),n,x)
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def A097184_list(prec):
P. = PowerSeriesRing(QQ, prec)
return P((1-(1-16*x)^(1/8))/(2*x)).list()
A097184_list(20) # G. C. Greubel, Sep 17 2019
A097183
Main diagonal of triangle A097181, in which the n-th row polynomial R_n(y) is formed from the initial (n+1) terms of g.f. A097182(y)^(n+1), where R_n(1/2) = 8^n for all n>=0.
Original entry on oeis.org
1, 14, 210, 3220, 49910, 778596, 12198004, 191682920, 3019005990, 47633205620, 752604648796, 11904837171864, 188493255221180, 2986893121197160, 47363590921840680, 751502309293205456, 11930099160029636614
Offset: 0
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R:=PowerSeriesRing(Rationals(), 20); Coefficients(R!( (1-16*x)^(-7/8) )); // G. C. Greubel, Sep 17 2019
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seq(coeff(series((1-16*x)^(-7/8), x, n+1), x, n), n = 0 ..20); # G. C. Greubel, Sep 17 2019
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Table[FullSimplify[(n+1)*16^n*Gamma[n+7/8]/(Gamma[7/8]*Gamma[n+2])], {n, 0, 20}] (* Vaclav Kotesovec, Feb 09 2014 *)
CoefficientList[Series[(1-16*x)^(-7/8), {x,0,20}], x] (* G. C. Greubel, Sep 17 2019 *)
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a(n)=polcoeff(1/(1-16*x+x*O(x^n))^(7/8),n,x)
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def A097183_list(prec):
P. = PowerSeriesRing(QQ, prec)
return P((1-16*x)^(-7/8)).list()
A097183_list(20) # G. C. Greubel, Sep 17 2019
A097185
Row sums of triangle A097181, in which the n-th row polynomial R_n(y) is formed from the initial (n+1) terms of g.f. A097182(y)^(n+1), where R_n(1/2) = 8^n for all n>=0.
Original entry on oeis.org
1, 15, 232, 3627, 57016, 899298, 14216560, 225110307, 3568890328, 56635884470, 899474459280, 14294357356110, 227286593929136, 3615608476770340, 57538659207907552, 915981394162628387, 14586262906867731096
Offset: 0
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R:=PowerSeriesRing(Rationals(), 30); Coefficients(R!( 2/((1-16*x) + (1-16*x)^(7/8)) )); // G. C. Greubel, Sep 17 2019
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seq(coeff(series(2/((1-16*x) + (1-16*x)^(7/8)), x, n+1), x, n), n = 0 ..30); # G. C. Greubel, Sep 17 2019
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CoefficientList[Series[2/((1-16*x) +(1-16*x)^(7/8)), {x,0,30}], x] (* G. C. Greubel, Sep 17 2019 *)
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a(n)=polcoeff(2/((1-16*x)+(1-16*x+x*O(x^n))^(7/8)),n,x)
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def A097185_list(prec):
P. = PowerSeriesRing(QQ, prec)
return P(2/((1-16*x) + (1-16*x)^(7/8))).list()
A097185_list(30) # G. C. Greubel, Sep 17 2019
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