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 1-5 of 5 results.

A298687 Numbers i such that Fibonacci(i) is divisible by i+k for k=0..5.

Original entry on oeis.org

13440, 19440, 329400, 600600, 2499840, 3150840, 5590200, 7660800, 69069000, 83980800, 96049800, 98385840, 175472640, 179663400, 237484800, 320498640, 330663600, 375396840, 404351640, 406380240, 429660000, 437940000, 505234800, 574585200, 635980800
Offset: 1

Views

Author

Alex Ratushnyak, Jan 24 2018

Keywords

Comments

A subsequence of A298686.

Crossrefs

Programs

  • Python
    p0 = 0
    p1 = 1
    for i in range(1,1000000):
      if p1 % i == 0 and p1 % (i+1) == 0 and p1 % (i+2) == 0:
         if p1 % (i+3) == 0 and p1 % (i+4) == 0 and p1 % (i+5) == 0:  print(i)
      p0, p1 = p1, p0+p1

Extensions

a(9)-a(25) from Chai Wah Wu, Jan 27 2018

A299155 Numbers i such that Fibonacci(i) is divisible by i+k for k=0..6.

Original entry on oeis.org

329400, 175472640, 808214400, 1367566200, 1928871000, 3433706640, 16109533440, 16916445000, 17847413640, 19507068000, 23163310800, 24961167000, 32645743200, 37263088800, 39803400000, 44915270400, 50238568800, 66072283200, 81924990840, 85368457440
Offset: 1

Views

Author

Chai Wah Wu, Feb 03 2018

Keywords

Comments

A subsequence of A298687.

Crossrefs

Programs

  • PARI
    fibomod(n,m) = lift(Mod([0,1;1,1],m)^(n+1))[1,1];
    isok(n) = prod(k=0,6,fibomod(n,n+k)==0); \\ Silvester Resnik, May 18 2018

Extensions

a(7)-a(20) from Silvester Resnik, May 18 2018

A298688 a(n) is the least i such that Fibonacci(i) is divisible by i+k for all k=0..n.

Original entry on oeis.org

1, 60, 60, 540, 13440, 13440, 329400, 175472640, 50238568800
Offset: 0

Views

Author

Alex Ratushnyak, Jan 24 2018

Keywords

Comments

a(0)..a(5) are first terms of sequences A023172, A217738, A298684, A298685, A298686, A298687.

Examples

			Least i such that Fibonacci(i) is divisible by i and i+1 (cf. A217738) is i=60, therefore a(1)=60.
Least i such that Fibonacci(i) is divisible by i, i+1, ..., i+5 (cf. A298687) is i=13440, therefore a(5)=13440.
		

Crossrefs

Extensions

a(7) from Alois P. Heinz, Jan 25 2018
a(6) inserted by Chai Wah Wu, Jan 26 2018
a(8) from Silvester Resnik, May 18 2018

A300555 Numbers i such that Fibonacci(i) is divisible by i+k for k = 0..7.

Original entry on oeis.org

175472640, 44915270400, 50238568800, 439287521400, 572836904640, 589596638400, 735284012400, 778042465200, 987189789600, 1261551677400, 1297640010240, 1307130728400, 1569978804240, 1979830125000, 2705598768600
Offset: 1

Views

Author

Silvester Resnik, May 19 2018

Keywords

Crossrefs

Programs

  • PARI
    fibomod(n, m) = lift(Mod([0, 1; 1, 1], m)^(n+1))[1, 1];
    isok(n) = prod(k=0, 7, fibomod(n, n+k)==0);

A303585 Numbers i such that Fibonacci(i) is divisible by i+k for k = 0..8.

Original entry on oeis.org

50238568800, 5824121940000, 46919196354240, 50564131254000, 80493123110400, 195778384956000, 307148642236800, 799863695270640
Offset: 1

Views

Author

Silvester Resnik, May 25 2018

Keywords

Crossrefs

Programs

  • PARI
    fibomod(n, m) = lift(Mod([0, 1; 1, 1], m)^(n+1))[1, 1];
    isok(n) = prod(k=0, 8, fibomod(n, n+k)==0);
Showing 1-5 of 5 results.