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.

A190491 a(n) = [(bn+c)r]-b[nr]-[cr], where (r,b,c)=(sqrt(2),3,1) and []=floor.

Original entry on oeis.org

1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 2, 3, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 1, 3, 1, 2, 0, 2, 0, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 2, 3, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 2, 3, 1, 2, 1, 2, 0, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 2, 3, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 2, 3, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 1, 3, 1, 2, 0, 2, 0, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 2, 3, 1, 2, 1, 2, 0, 1, 3, 1, 2, 0, 2, 3, 1, 2, 0, 2, 0
Offset: 1

Views

Author

Clark Kimberling, May 11 2011

Keywords

Comments

Write a(n)=[(bn+c)r]-b[nr]-[cr]. If r>0 and b and c are integers satisfying b>=2 and 0<=c<=b-1, then 0<=a(n)<=b. The positions of 0 in the sequence a are of interest, as are the position sequences for 1,2,...,b. These b+1 position sequences comprise a partition of the positive integers.
Examples:
(golden ratio,2,1): A190427-A190430
(sqrt(2),2,0): A190480, A120743, A170749
(sqrt(2),2,1): A190483-A190486
(sqrt(2),3,0): A190487-A190490
(sqrt(2),3,1): A190491-A190495
(sqrt(2),3,2): A190496-A190500

Crossrefs

Programs

  • Mathematica
    r = Sqrt[2]; b = 3; c = 1;
    f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r];
    t = Table[f[n], {n, 1, 200}]  (* A190491 *)
    Flatten[Position[t, 0]]   (* A190492 *)
    Flatten[Position[t, 1]]   (* A190493 *)
    Flatten[Position[t, 2]]   (* A190494 *)
    Flatten[Position[t, 3]]   (* A190495 *)

A221131 Table, T, read by antidiagonals where T(-j,k) = ((1+sqrt(j))^k + (1-sqrt(j))^k)/2.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, -1, -2, 1, 1, 1, -2, -5, -4, 1, 1, 1, -3, -8, -7, -4, 1, 1, 1, -4, -11, -8, 1, 0, 1, 1, 1, -5, -14, -7, 16, 23, 8, 1, 1, 1, -6, -17, -4, 41, 64, 43, 16, 1, 1, 1, -7, -20, 1, 76, 117, 64, 17, 16, 1, 1, 1, -8, -23, 8, 121, 176, 29, -128, -95, 0, 1
Offset: 0

Views

Author

Al Hakanson (hawkuu(AT)gmail.com) and Robert G. Wilson v, Jan 02 2013

Keywords

Comments

.j\k.........0..1...2....3...4....5....6......7.......8......9......10
.0: A000012..1..1...1....1...1....1....1......1.......1......1.......1
-1: A146559..1..1...0...-2..-4...-4....0......8......16.....16.......0
-2: A087455..1..1..-1...-5..-7....1...23.....43......17....-95....-241
-3: A138230..1..1..-2...-8..-8...16...64.....64....-128...-512....-512
-4: A006495..1..1..-3..-11..-7...41..117.....29....-527..-1199.....237
-5: A138229..1..1..-4..-14..-4...76..176...-104...-1264..-1904....3776
-6: A090592..1..1..-5..-17...1..121..235...-377...-2399..-2159...12475
-7: A090590..1..1..-6..-20...8..176..288...-832...-3968..-1280...29184
-8: A025172..1..1..-7..-23..17..241..329..-1511...-5983...1633...57113
-9: A120743..1..1..-8..-26..28..316..352..-2456...-8432...7696...99712
-10: ........1..1..-9..-29..41..401..351..-3709..-11279..18241..160551

Crossrefs

Programs

  • Mathematica
    T[j_, k_] := Expand[((1 + Sqrt[j])^k + (1 - Sqrt[j])^k)/2]; Table[ T[ -j + k, k], {j, 0, 11}, {k, 0, j}] // Flatten
Showing 1-2 of 2 results.