cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 23 results. Next

A112127 G.f. A(x) satisfies A(A(A(..(A(x))..))) = B(x) (13th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,..,13}, with B(0) = 0.

Original entry on oeis.org

1, 1, -11, 193, -4043, 92233, -2188907, 52544305, -1250612651, 29060631481, -651497950667, 13997025548641, -289196932607819, 5873067677083177, -122109541297984368, 2669034419647762122, -58550172867811577842, 1127335101086707607932
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			A(x) = x + x^2 - 11*x^3 + 193*x^4 - 4043*x^5 + 92233*x^6 +...
where A(A(A(A(A(A(A(A(A(A(A(A(A(x))))))))))))) =
x + 13*x^2 + 13*x^3 + 13*x^4 + 13*x^5 + 13*x^6 + 13*x^7 +...
is the g.f. of A112126.
		

Crossrefs

Programs

  • PARI
    {a(n,m=13)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}

A112105 G.f. A(x) satisfies A(A(x)) = B(x) such that the coefficients of B(x) consist of all 1's and 2's, with A(0) = 0.

Original entry on oeis.org

1, 1, 0, 0, 1, -3, 7, -10, -5, 84, -248, 90, 2160, -7541, -5846, 122824, -186259, -2036532, 8665409, 36714511, -345711246, -517802065, 14415153844, -9423161197, -653074772917, 1896978939457, 32374651932128, -184814895196023, -1733326272860598, 16839263882542991, 96742403684106435
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			A(x) = x + x^2 + x^5 - 3*x^6 + 7*x^7 - 10*x^8 - 5*x^9 +...
where A(A(x)) = x + 2*x^2 + 2*x^3 + x^4 + 2*x^5 + x^6 +... is the g.f. of A112104.
		

Crossrefs

Programs

  • Mathematica
    kmax = 40;
    A[x_] := Sum[a[k] x^k, {k, kmax}];
    B[x_] := Sum[b[k] x^k, {k, kmax}];
    sol = {a[1] -> 1, b[1] -> 1};
    Do[sc = SeriesCoefficient[A[(A[x] /. sol) + O[x]^(k+1)] - B[x], {x, 0, k}] /. sol; r = Reduce[(b[k] == 1 || b[k] == 2) && sc == 0, {a[k], b[k]}, Integers]; sol = Join[r // ToRules, sol], {k, 2, kmax}];
    a /@ Range[kmax] /. sol (* Jean-François Alcover, Nov 05 2019 *)
  • PARI
    {a(n,m=2)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}

A112117 G.f. A(x) satisfies A(A(A(..(A(x))..))) = B(x) (8th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,..,8}, with B(0) = 0.

Original entry on oeis.org

1, 1, -6, 60, -720, 9398, -126958, 1719439, -22778647, 288721672, -3426131120, 37291873546, -368633930696, 3421668183648, -33763691015949, 382711017377914, -3403489111329505, -22613095886515578, 1672401759052466166, -27936127591842262118, -15637150116164531317
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			A(x) = x + x^2 - 6*x^3 + 60*x^4 - 720*x^5 + 9398*x^6 +...
where A(A(A(A(A(A(A(A(x)))))))) =
x + 8*x^2 + 8*x^3 + 4*x^4 + 8*x^5 + 4*x^6 + 8*x^7 +...
is the g.f. of A112116.
		

Crossrefs

Programs

  • PARI
    {a(n,m=8)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}

A112106 Unique sequence of numbers {1,2,3} where g.f. A(x) satisfies A(x) = B(B(B(x))) (3rd self-COMPOSE) such that B(x) is an integer series, with A(0) = 0.

Original entry on oeis.org

1, 3, 3, 3, 2, 2, 1, 2, 1, 3, 1, 1, 3, 3, 3, 2, 3, 3, 2, 2, 2, 1, 2, 2, 3, 1, 2, 1, 1, 2, 3, 2, 2, 2, 1, 2, 2, 3, 2, 2, 2, 1, 1, 1, 1, 2, 3, 2, 1, 2, 3, 2, 3, 2, 2, 3, 2, 3, 3, 2, 3, 3, 3, 1, 3, 2, 1, 3, 2, 2, 1, 2, 3, 1, 3, 1, 3, 1, 1, 1, 3, 1, 2, 3, 3, 3, 3, 3, 3, 1, 1, 2, 2, 3, 3, 1, 3, 2, 1, 2, 2, 1, 1, 3, 1
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			G.f.: A(x) = x + 3*x^2 + 3*x^3 + 3*x^4 + 2*x^5 + 2*x^6 + ...
then A(x) = B(B(B(x))) where
B(x) = x + x^2 - x^3 + 3*x^4 - 10*x^5 + 35*x^6 - 119*x^7 + ...
is the g.f. of A112107.
		

Crossrefs

Programs

  • PARI
    {a(n,m=3)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); G=F+x*O(x^n);for(i=1,m-1,G=subst(F,x,G)); return(polcoeff(G,n,x)))}

A112107 G.f. A(x) satisfies A(A(A(x))) = B(x) (3rd self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3}, with B(0) = 0.

Original entry on oeis.org

1, 1, -1, 3, -10, 35, -119, 360, -792, -33, 12779, -82525, 305861, -552011, -126321, -8385020, 138177591, -433073834, -5366414982, 51203452090, 123835509276, -4174647911014, 5274854624423, 373574363131841, -2054088594386738, -34047892948849106, 391005463740951942
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			A(x) = x + x^2 - x^3 + 3*x^4 - 10*x^5 + 35*x^6 - 119*x^7 + ...
where A(A(A(x))) = x + 3*x^2 + 3*x^3 + 3*x^4 + 2*x^5 + ...
is the g.f. of A112106.
		

Crossrefs

Programs

  • PARI
    {a(n,m=3)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}

A112108 Unique sequence of numbers {1,2,3,4} where g.f. A(x) satisfies A(x) = B(B(B(B(x)))) (4th self-COMPOSE) such that B(x) is an integer series, with A(0) = 0.

Original entry on oeis.org

1, 4, 4, 2, 4, 2, 4, 4, 2, 4, 4, 2, 2, 4, 4, 2, 2, 4, 4, 3, 4, 3, 2, 4, 1, 2, 4, 2, 3, 1, 4, 2, 4, 3, 1, 4, 4, 4, 2, 2, 2, 3, 3, 2, 3, 2, 2, 4, 1, 4, 2, 2, 1, 4, 3, 3, 3, 1, 1, 3, 3, 4, 4, 3, 3, 3, 3, 1, 4, 4, 3, 2, 4, 2, 2, 2, 1, 3, 4, 2, 3, 3, 1, 4, 2, 3, 1, 1, 3, 3, 4, 2, 4, 3, 1, 4, 3, 2, 1, 1, 1, 2, 1, 4, 4
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			G.f.: A(x) = x + 4*x^2 + 4*x^3 + 2*x^4 + 4*x^5 + 2*x^6 + ...
then A(x) = B(B(B(B(x)))) where
B(x) = x + x^2 - 2*x^3 + 8*x^4 - 38*x^5 + 194*x^6 - 992*x^7 + ...
is the g.f. of A112109.
		

Crossrefs

Programs

  • PARI
    {a(n,m=4)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); G=F+x*O(x^n);for(i=1,m-1,G=subst(F,x,G)); return(polcoeff(G,n,x)))}

A112109 G.f. A(x) satisfies A(A(A(A(x)))) = B(x) (4th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,4}, with B(0) = 0.

Original entry on oeis.org

1, 1, -2, 8, -38, 194, -992, 4777, -19831, 56116, 48008, -2062286, 16053636, -70193968, 155216743, -968038798, 23817048561, -233579083166, 333773365, 21684104628935, -121906541882294, -2171063003748135, 30425707365005935, 192144123118329872
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			A(x) = x + x^2 - 2*x^3 + 8*x^4 - 38*x^5 + 194*x^6 - 992*x^7 +...
where A(A(A(A(x)))) =
x + 4*x^2 + 4*x^3 + 2*x^4 + 4*x^5 + 2*x^6 + 4*x^7 + 4*x^8 +...
is the g.f. of A112108.
		

Crossrefs

Programs

  • PARI
    {a(n,m=4)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}

A112110 Unique sequence of numbers {1,2,3,4,5} where g.f. A(x) satisfies A(x) = B(B(B(B(B(x))))) (5th self-COMPOSE) such that B(x) is an integer series, with A(0) = 0.

Original entry on oeis.org

1, 5, 5, 5, 5, 5, 4, 4, 4, 4, 3, 1, 1, 1, 5, 3, 1, 1, 5, 3, 4, 3, 2, 1, 5, 4, 1, 4, 1, 5, 1, 4, 5, 4, 2, 1, 5, 2, 5, 4, 5, 5, 4, 1, 1, 5, 4, 3, 5, 1, 5, 2, 2, 3, 1, 3, 2, 5, 2, 5, 3, 2, 3, 5, 2, 1, 2, 3, 1, 5, 1, 4, 5, 4, 3, 3, 2, 4, 2, 3, 4, 5, 2, 5, 5, 2, 4, 2, 3, 5, 3, 2, 4, 2, 2, 1, 1, 2, 3, 4, 5, 3, 3, 1, 5
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			G.f.: A(x) = x + 5*x^2 + 5*x^3 + 5*x^4 + 5*x^5 + 5*x^6 + ...
then A(x) = B(B(B(B(B(x))))) where
B(x) = x + x^2 - 3*x^3 + 17*x^4 - 115*x^5 + 841*x^6 + ...
is the g.f. of A112111.
		

Crossrefs

Programs

  • PARI
    {a(n,m=5)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); G=F+x*O(x^n);for(i=1,m-1,G=subst(F,x,G)); return(polcoeff(G,n,x)))}

A112111 G.f. A(x) satisfies A(A(A(A(A(x))))) = B(x) (5th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,4,5}, with B(0) = 0.

Original entry on oeis.org

1, 1, -3, 17, -115, 841, -6288, 46174, -320366, 1997348, -10216611, 32418767, 68603755, -1909624513, 15239954041, -103620859984, 1499179409198, -25808959095992, 258001631302410, -239530586418995, -25424691109062239, 84868851253494310
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			A(x) = x + x^2 - 3*x^3 + 17*x^4 - 115*x^5 + 841*x^6 -6288*x^7 +...
where A(A(A(A(A(x))))) =
x + 5*x^2 + 5*x^3 + 5*x^4 + 5*x^5 + 5*x^6 + 4*x^7 + 3*x^8 +...
is the g.f. of A112110.
		

Crossrefs

Programs

  • PARI
    {a(n,m=5)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); return(polcoeff(F,n,x)))}

A112112 Unique sequence of numbers {1,2,3,...,6} where g.f. A(x) satisfies A(x) = B(B(B(..(B(x))..))) (6th self-COMPOSE) such that B(x) is an integer series, with A(0) = 0.

Original entry on oeis.org

1, 6, 6, 3, 4, 4, 6, 2, 5, 3, 3, 5, 3, 2, 5, 3, 3, 4, 5, 4, 3, 2, 6, 4, 3, 6, 2, 5, 6, 4, 2, 5, 4, 5, 1, 1, 1, 4, 4, 2, 3, 6, 6, 5, 5, 4, 3, 5, 5, 2, 2, 1, 3, 6, 1, 5, 2, 6, 5, 4, 3, 4, 6, 6, 5, 5, 6, 1, 5, 6, 6, 3, 3, 1, 5, 4, 5, 1, 5, 2, 2, 4, 3, 4, 2, 1, 6, 1, 3, 2, 4, 1, 3, 5, 3, 1, 3, 2, 6, 2, 5, 1, 3, 6, 2
Offset: 1

Views

Author

Paul D. Hanna, Aug 27 2005

Keywords

Examples

			G.f.: Let A(x) = x + 6*x^2 + 6*x^3 + 3*x^4 + 4*x^5 + 4*x^6 + ...
then A(x) = B(B(B(B(B(B(x)))))) where B(x) = x + x^2 - 4*x^3 + 28*x^4 - 236*x^5 + 2159*x^6 + ... is the g.f. of A112113.
		

Crossrefs

Programs

  • PARI
    {a(n,m=6)=local(F=x+x^2+x*O(x^n),G);if(n<1,0, for(k=3,n, G=F+x*O(x^k);for(i=1,m-1,G=subst(F,x,G)); F=F-((polcoeff(G,k)-1)\m)*x^k); G=F+x*O(x^n);for(i=1,m-1,G=subst(F,x,G)); return(polcoeff(G,n,x)))}
Showing 1-10 of 23 results. Next