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 1-4 of 4 results.

A059564 Beatty sequence for (e^2 + 1)/(e^2 - e + 1).

Original entry on oeis.org

1, 2, 4, 5, 7, 8, 10, 11, 13, 14, 16, 17, 19, 20, 22, 23, 25, 26, 28, 29, 31, 32, 34, 35, 36, 38, 39, 41, 42, 44, 45, 47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 65, 66, 68, 69, 71, 72, 73, 75, 76, 78, 79, 81, 82, 84, 85, 87, 88, 90, 91, 93, 94, 96, 97, 99, 100, 102, 103
Offset: 1

Views

Author

Mitch Harris, Jan 22 2001

Keywords

Crossrefs

Beatty complement is A059563.

Programs

  • Maple
    A059564:=n->floor(n*(exp(1)^2+1)/(exp(1)^2-exp(1)+1)): seq(A059564(n), n=1..100); # Wesley Ivan Hurt, Jan 03 2016
  • Mathematica
    Table[Floor[n (E^2 + 1)/(E^2 - E + 1)], {n, 80}] (* Wesley Ivan Hurt, Jan 03 2016 *)
  • PARI
    { default(realprecision, 100); e=exp(1); b=(e^2 + 1)/(e^2 - e + 1); for (n = 1, 2000, write("b059564.txt", n, " ", floor(n*b)); ) } \\ Harry J. Smith, Jun 28 2009

Formula

a(n) = floor(n*(e^2+1)/(e^2-e+1)). - Michel Marcus, Jan 05 2015

A109231 a(n) = floor(n*cosh(1)).

Original entry on oeis.org

1, 3, 4, 6, 7, 9, 10, 12, 13, 15, 16, 18, 20, 21, 23, 24, 26, 27, 29, 30, 32, 33, 35, 37, 38, 40, 41, 43, 44, 46, 47, 49, 50, 52, 54, 55, 57, 58, 60, 61, 63, 64, 66, 67, 69, 70, 72, 74, 75, 77, 78, 80, 81, 83, 84, 86, 87, 89, 91, 92, 94, 95, 97, 98, 100
Offset: 1

Views

Author

Reinhard Zumkeller, Jun 23 2005

Keywords

Comments

Beatty sequence for cosh(1) = (e+1/e)/2 = 1.54308...= A073743; complement of A109232.

Crossrefs

A127451 Beatty sequence for 1/(1 - e^Pi + Pi^e), complement of A127450.

Original entry on oeis.org

3, 6, 9, 12, 15, 18, 21, 25, 28, 31, 34, 37, 40, 43, 47, 50, 53, 56, 59, 62, 65, 69, 72, 75, 78, 81, 84, 87, 91, 94, 97, 100, 103, 106, 109, 113, 116, 119, 122, 125, 128, 131, 135, 138, 141, 144, 147, 150, 153, 157, 160, 163, 166, 169, 172, 175, 178, 182, 185, 188
Offset: 1

Views

Author

Robert G. Wilson v, Jan 14 2007

Keywords

Comments

Differs from A022844 first at a(57). - L. Edson Jeffery, Dec 01 2013
1/(1 - e^Pi + Pi^e) = 3.140061643.., so a(n)<=A022844(n). - R. J. Mathar, May 30 2025

Crossrefs

Programs

  • Mathematica
    Table[Floor[n/(1 - Exp[Pi] + Pi^E)], {n, 60}]

Formula

a(n) = floor(n/(1 - e^Pi + Pi^e))

A380408 a(n) = Sum_{k>=0} floor(n/(2k)!).

Original entry on oeis.org

0, 1, 3, 4, 6, 7, 9, 10, 12, 13, 15, 16, 18, 19, 21, 22, 24, 25, 27, 28, 30, 31, 33, 34, 37, 38, 40, 41, 43, 44, 46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 61, 62, 64, 65, 67, 68, 70, 71, 74, 75, 77, 78, 80, 81, 83, 84, 86, 87, 89, 90, 92, 93, 95, 96, 98, 99, 101, 102, 104, 105, 107
Offset: 0

Views

Author

Akiva Weinberger, Jan 23 2025

Keywords

Comments

Partial sum of A060832 except for the first term in the sum.
Congruent to A034968(n) mod 2. Therefore, the parity of a(n) is the parity of the n-th permutation of k elements (k>=n) in lexicographic order.
For even n, a(n) equals A059563(n/2) whenever cosh(1)*n - a(n) < 1. The first time this fails is n=70, as a(70)=107 but A059563(35)=108. For small n, such failures appear to be very rare; however, the asymptotic density of these failures approaches 1.

Crossrefs

Programs

  • PARI
    a(n) = round(sumpos(k=0, n\(2*k)!)); \\ Michel Marcus, Jan 24 2025

Formula

a(n) = cosh(1)*n - f(n) where f(n) = Sum_{k>=0} fract(n/(2k)!). Here, fract() is the fractional part. The error term f(n) is unbounded above, and the greatest lower bound is 0 (even excluding n=0). The first values for which f(n) > s for s=1,2,3 are f(13)=1.06005, f(407) = 2.03382, and f(22319) = 3.01669. The error is almost periodic: for large m, f(n) is approximately f(n+(2m)!). If n is odd, f(n) > 1/2. f(n) alternately rises and descends, that is, f(2*n)f(2*n+2) for all n.
Showing 1-4 of 4 results.