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 1-3 of 3 results.

A079370 Records in A079369.

Original entry on oeis.org

2, 3, 5, 11, 17, 37, 53, 73, 79, 277, 2903, 9463, 24631, 202049
Offset: 1

Views

Author

N. J. A. Sloane, Feb 16 2003

Keywords

Comments

RECORDS transform of A079369.

Links

Crossrefs

Cf. A079369, A079371, A079366-A079368.

Programs

  • Mathematica
    A079369 = Cases[Import["https://oeis.org/A079369/b079369.txt", "Table"], {, }][[All, 2]];
a = {}; l = 0;
For[i = 1, i <= Length[A079369], i++,
  If[A079369[[i]] > l, l = A079369[[i]]; AppendTo[a, l]]];
a (* Robert Price, Mar 14 2020 *)

Extensions

a(13)-a(14) from Robert Price, Mar 14 2020

A079371 Where records occur in A079369.

Original entry on oeis.org

1, 2, 3, 5, 6, 9, 19, 23, 25, 35, 36, 42, 976, 977
Offset: 1

Views

Author

N. J. A. Sloane, Feb 16 2003

Keywords

Comments

RECORDS transform of A079369.

Links

Crossrefs

Cf. A079369, A079370, A079366-A079368.

Programs

  • Mathematica
    A079369 = Cases[Import["https://oeis.org/A079369/b079369.txt", "Table"], {, }][[All, 2]];
a = {}; l = 0;
For[i = 1, i <= Length[A079369], i++,
  If[A079369[[i]] > l, l = A079369[[i]]; AppendTo[a, i]]];
a (* Robert Price, Mar 14 2020 *)

Extensions

a(13)-a(14) from Robert Price, Mar 14 2020

A079366 Costé prime expansion of Pi - 3.

Original entry on oeis.org

11, 2, 11, 5, 5, 2, 5, 3, 17, 11, 3, 3, 11, 3, 3, 11, 5, 3, 23, 7, 5, 97, 29, 37, 107, 127, 29, 17, 409, 127, 11, 29, 5, 67, 19, 43, 31, 19, 103, 59, 29, 7, 3, 11, 11, 5, 47, 29, 11, 3, 5, 5, 3, 17, 5, 29, 11, 3, 3, 3, 3, 5, 5, 61, 151, 58889, 1877, 983, 757, 163
Offset: 0

Views

Author

N. J. A. Sloane, Feb 15 2003

Keywords

Comments

For x in (0,1], define P(x) = min{p: p prime, 1/x < p}, Phi(x) = P(x)x - 1. Costé prime expansion of x(0) is sequence a(0), a(1), ... given by x(n) = Phi(x(n-1)) (n>0), a(n) = P(x(n)) (n >= 0).
Costé prime expansion = Engel expansion where all terms must be primes (cf. A006784).

Links

Crossrefs

Cf. A079367, A079368. Also A079369-A079389.

Programs

  • Maple
    Digits := 200: P := proc(x) local y; y := ceil(evalf(1/x)); if isprime(y) then y else nextprime(y); fi; end; F := proc(x) local y,i,t1; y := x; t1 := []; for i from 1 to 50 do p := P(y); t1 := [op(t1),p]; y := p*y-1; od; t1; end; F(Pi-3);
  • Mathematica
    $MaxExtraPrecision = 40; P[x_] := Module[{y}, y = Ceiling[1/x]; If[PrimeQ[y], y, NextPrime[y]]]; F[x_] := Module[{y, i, t1}, y = x; t1 = {}; For[i = 1, i <= 70, i++, AppendTo[t1, p = P[y]]; y = p*y-1]; t1]; F[Pi-3] (* Jean-François Alcover, Dec 16 2013, translated from Maple *)
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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