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.

Previous Showing 11-13 of 13 results.

A047365 Numbers that are congruent to {0, 3, 4, 5} mod 7.

Original entry on oeis.org

0, 3, 4, 5, 7, 10, 11, 12, 14, 17, 18, 19, 21, 24, 25, 26, 28, 31, 32, 33, 35, 38, 39, 40, 42, 45, 46, 47, 49, 52, 53, 54, 56, 59, 60, 61, 63, 66, 67, 68, 70, 73, 74, 75, 77, 80, 81, 82, 84, 87, 88, 89, 91, 94, 95, 96, 98, 101, 102, 103, 105, 108, 109, 110
Offset: 1

Views

Author

Keywords

Crossrefs

Programs

  • Magma
    [n : n in [0..150] | n mod 7 in [0, 3, 4, 5]]; // Wesley Ivan Hurt, Jun 04 2016
  • Maple
    A047365:=n->(14*n-11+I^(2*n)-(3+I)*I^(-n)-(3-I)*I^n)/8: seq(A047365(n), n=1..100); # Wesley Ivan Hurt, Jun 04 2016
  • Mathematica
    Select[Range[0,100], MemberQ[{0,3,4,5}, Mod[#,7]]&] (* or *) LinearRecurrence[{1,0,0,1,-1}, {0,3,4,5,7}, 60] (* Harvey P. Dale, May 26 2012 *)

Formula

G.f.: x^2*(3+x+x^2+2*x^3) / ( (1+x)*(x^2+1)*(x-1)^2 ). - R. J. Mathar, Dec 04 2011
a(1)=0, a(2)=3, a(3)=4, a(4)=5, a(5)=7, a(n)=a(n-1)+a(n-4)-a(n-5) for n>5. - Harvey P. Dale, May 26 2012
From Wesley Ivan Hurt, Jun 04 2016: (Start)
a(n) = (14*n-11+i^(2*n)-(3+i)*i^(-n)-(3-i)*i^n)/8 where i=sqrt(-1).
a(2k) = A047389(k), a(2k-1) = A047345(k). (End)

A047377 Numbers that are congruent to {0, 1, 4, 5} mod 7.

Original entry on oeis.org

0, 1, 4, 5, 7, 8, 11, 12, 14, 15, 18, 19, 21, 22, 25, 26, 28, 29, 32, 33, 35, 36, 39, 40, 42, 43, 46, 47, 49, 50, 53, 54, 56, 57, 60, 61, 63, 64, 67, 68, 70, 71, 74, 75, 77, 78, 81, 82, 84, 85, 88, 89, 91, 92, 95, 96, 98, 99, 102, 103, 105, 106, 109, 110
Offset: 1

Views

Author

Keywords

Crossrefs

Programs

  • Magma
    [n : n in [0..150] | n mod 7 in [0, 1, 4, 5]]; // Wesley Ivan Hurt, May 24 2016
  • Maple
    A047377:=n->(14*n-15-3*I^(2*n)+(1-I)*I^(-n)+(1+I)*I^n)/8: seq(A047377(n), n=1..100); # Wesley Ivan Hurt, May 24 2016
  • Mathematica
    Table[(14n-15-3*I^(2n)+(1-I)*I^(-n)+(1+I)*I^n)/8, {n, 80}] (* Wesley Ivan Hurt, May 24 2016 *)
    Select[Range@ 120, MemberQ[{0, 1, 4, 5}, Mod[#, 7]] &] (* Michael De Vlieger, May 24 2016 *)
    a[n_] :=  n + Floor[(n - 1)/2] +  Floor[(n - 3)/4];
    Table[a[n], {n, 1, 64}] (* Peter Luschny, Dec 23 2021 *)

Formula

a(n+1) = Sum_{k>=0} A030308(n,k)*b(k) with b(0)=1, b(1)=4 and b(k)=7*2^(k-2) for k>1. - Philippe Deléham, Oct 25 2011
G.f.: x^2*(1+3*x+x^2+2*x^3) / ( (1+x)*(x^2+1)*(x-1)^2 ). - R. J. Mathar, Dec 04 2011
From Wesley Ivan Hurt, May 24 2016: (Start)
a(n) = a(n-1) + a(n-4) - a(n-5) for n>5.
a(n) = (14*n-15-3*i^(2*n)+(1-i)*i^(-n)+(1+i)*i^n)/8, where i=sqrt(-1).
a(2k) = A047383(k), a(2k-1) = A047345(k). (End)
E.g.f.: (8 - sin(x) + cos(x) + (7*x - 6)*sinh(x) + (7*x - 9)*cosh(x))/4. - Ilya Gutkovskiy, May 25 2016

Extensions

More terms from Wesley Ivan Hurt, May 24 2016

A198269 Ceiling(n*sqrt(12)).

Original entry on oeis.org

0, 4, 7, 11, 14, 18, 21, 25, 28, 32, 35, 39, 42, 46, 49, 52, 56, 59, 63, 66, 70, 73, 77, 80, 84, 87, 91, 94, 97, 101, 104, 108, 111, 115, 118, 122, 125, 129, 132, 136, 139, 143, 146, 149, 153, 156, 160, 163, 167, 170, 174, 177, 181, 184, 188
Offset: 0

Views

Author

Vincenzo Librandi, Oct 24 2011

Keywords

Crossrefs

Programs

  • Magma
    [Ceiling(n*Sqrt(12)): n in [0..60]]
  • Mathematica
    Ceiling[Sqrt[12]Range[0,60]] (* Harvey P. Dale, Aug 27 2013 *)
Previous Showing 11-13 of 13 results.