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 1-2 of 2 results.

A367328 The x-coordinate of the point where x + y = n, x and y are integers and x/y is as close as possible to e.

Original entry on oeis.org

0, 1, 2, 3, 3, 4, 5, 6, 6, 7, 8, 9, 9, 10, 11, 12, 12, 13, 14, 15, 15, 16, 17, 18, 18, 19, 20, 20, 21, 22, 23, 23, 24, 25, 26, 26, 27, 28, 28, 29, 30, 31, 31, 32, 33, 34, 34, 35, 36, 37, 37, 38, 39, 39, 40, 41, 42, 42, 43, 44, 45, 45, 46, 47, 48, 48, 49, 50
Offset: 1

Views

Author

Colin Linzer, Nov 14 2023

Keywords

Comments

a(n) is nondecreasing; lim_{n->oo} a(n) = oo.
Swapping the x and y coordinate of the sequence does not yield the sequence defined as the point where x + y = n, x and y are integers and x/y is as close as possible to 1/e even when excluding terms that would lead to a division by 0.

Examples

			For n = 3, the possible points are (0,3), (1,2), (2,1) as any negative value would would be further from e than 0/3. The closest value to e out of these is 2/1 so a(3) = 2.
		

Crossrefs

Cf. A001113 (e), A367329 (y-coordinate), A007676.

Formula

a(n) is always either ceiling(n*e/(1 + e)) or floor(n*e/(1 + e)) = A076538(n).

A370325 Decimal expansion of exp(1)/(1+exp(1)).

Original entry on oeis.org

7, 3, 1, 0, 5, 8, 5, 7, 8, 6, 3, 0, 0, 0, 4, 8, 7, 9, 2, 5, 1, 1, 5, 9, 2, 4, 1, 8, 2, 1, 8, 3, 6, 2, 7, 4, 3, 6, 5, 1, 4, 4, 6, 4, 0, 1, 6, 5, 0, 5, 6, 5, 1, 9, 2, 7, 6, 3, 6, 5, 9, 0, 7, 9, 1, 9, 0, 4, 0, 4, 5, 3, 0, 7, 0, 2, 0, 4, 6, 3, 9, 3, 8, 7, 4, 7, 4, 5, 3, 2, 0, 7, 5, 9, 8, 1
Offset: 0

Views

Author

R. J. Mathar, Feb 15 2024

Keywords

Examples

			0.73105857863000487925115924182183627...
		

Crossrefs

Cf. A076538 (Beatty seq.), A001113, A201776, A068985.

Programs

  • Maple
    exp(1)/(1+exp(1)) ; evalf(%) ;
  • Mathematica
    RealDigits[E/(E + 1), 10, 120][[1]] (* Amiram Eldar, Feb 18 2024 *)
  • PARI
    exp(1)/(exp(1)+1) \\ Amiram Eldar, Feb 18 2024

Formula

Equals A001113*A201776 = 1/(1 + A068985).
Equals 1/(1 + Sum_{k>=0} (-1)^k/k!). - Peter Luschny, Feb 15 2024
Showing 1-2 of 2 results.