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.

Previous Showing 31-34 of 34 results.

A276181 Fricke's 37 cases for two-valued modular equations.

Original entry on oeis.org

2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 29, 31, 32, 35, 36, 39, 41, 47, 49, 50, 59, 71
Offset: 1

Views

Author

Gheorghe Coserea, Oct 17 2016

Keywords

Crossrefs

Programs

  • PARI
    A000003(n) = qfbclassno(-4*n);
    A000089(n) = {
      if (n%4 == 0 || n%4 == 3, return(0));
      if (n%2 == 0, n \= 2);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 4 == 3, 0, 2));
    };
    A000086(n) = {
      if (n%9 == 0 || n%3 == 2, return(0));
      if (n%3 == 0, n \= 3);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 3 == 2, 0, 2));
    };
    A001615(n) = {
      my(f = factor(n), fsz = matsize(f)[1],
         g = prod(k=1, fsz, (f[k, 1]+1)),
         h = prod(k=1, fsz, f[k, 1]));
      return((n*g)\h);
    };
    A001616(n) = {
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, f[k, 1]^(f[k, 2]\2) + f[k, 1]^((f[k, 2]-1)\2));
    };
    A001617(n) = 1 + A001615(n)/12 - A000089(n)/4 - A000086(n)/3 - A001616(n)/2;
    A276183(n) = {
      my(r = if (n%8 == 3, 4, n%8 == 7, 6, 3));
      if (n < 5, 0, (1 + A001617(n))/2 -  r * A000003(n)/12);
    };
    select(x->(x>1), Vec(select(x->x==0, vector(100, n, A276183(n)), 1)))

Formula

Numbers n>1 such that 0 = A276183(n).

A276184 Numbers n such that A276183(n) = 1.

Original entry on oeis.org

22, 28, 30, 33, 34, 37, 38, 40, 43, 44, 45, 48, 51, 53, 54, 55, 56, 61, 63, 64, 65, 75, 79, 81, 83, 89, 95, 101, 119, 131
Offset: 1

Views

Author

Gheorghe Coserea, Oct 22 2016

Keywords

Crossrefs

Cf. A276183.

Programs

  • PARI
    A000003(n) = qfbclassno(-4*n);
    A000089(n) = {
      if (n%4 == 0 || n%4 == 3, return(0));
      if (n%2 == 0, n \= 2);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 4 == 3, 0, 2));
    };
    A000086(n) = {
      if (n%9 == 0 || n%3 == 2, return(0));
      if (n%3 == 0, n \= 3);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 3 == 2, 0, 2));
    };
    A001615(n) = {
      my(f = factor(n), fsz = matsize(f)[1],
         g = prod(k=1, fsz, (f[k, 1]+1)),
         h = prod(k=1, fsz, f[k, 1]));
      return((n*g)\h);
    };
    A001616(n) = {
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, f[k, 1]^(f[k, 2]\2) + f[k, 1]^((f[k, 2]-1)\2));
    };
    A001617(n) = 1 + A001615(n)/12 - A000089(n)/4 - A000086(n)/3 - A001616(n)/2;
    A276183(n) = {
      my(r = if (n%8 == 3, 4, n%8 == 7, 6, 3));
      if (n < 5, 0, (1 + A001617(n))/2 -  r * A000003(n)/12);
    };
    Vec(select(x->x==1, vector(5000, n, A276183(n)), 1))

A276185 Numbers n such that A276183(n) = 2.

Original entry on oeis.org

42, 46, 52, 57, 62, 67, 68, 69, 72, 73, 74, 77, 80, 87, 91, 98, 103, 107, 111, 121, 125, 143, 167, 191
Offset: 1

Views

Author

Gheorghe Coserea, Oct 22 2016

Keywords

Crossrefs

Cf. A276183.

Programs

  • PARI
    A000003(n) = qfbclassno(-4*n);
    A000089(n) = {
      if (n%4 == 0 || n%4 == 3, return(0));
      if (n%2 == 0, n \= 2);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 4 == 3, 0, 2));
    };
    A000086(n) = {
      if (n%9 == 0 || n%3 == 2, return(0));
      if (n%3 == 0, n \= 3);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 3 == 2, 0, 2));
    };
    A001615(n) = {
      my(f = factor(n), fsz = matsize(f)[1],
         g = prod(k=1, fsz, (f[k, 1]+1)),
         h = prod(k=1, fsz, f[k, 1]));
      return((n*g)\h);
    };
    A001616(n) = {
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, f[k, 1]^(f[k, 2]\2) + f[k, 1]^((f[k, 2]-1)\2));
    };
    A001617(n) = 1 + A001615(n)/12 - A000089(n)/4 - A000086(n)/3 - A001616(n)/2;
    A276183(n) = {
      my(r = if (n%8 == 3, 4, n%8 == 7, 6, 3));
      if (n < 5, 0, (1 + A001617(n))/2 -  r * A000003(n)/12);
    };
    Vec(select(x->x==2, vector(500, n, A276183(n)), 1))

A276186 Numbers n such that A276183(n) = 3.

Original entry on oeis.org

58, 60, 66, 76, 85, 86, 96, 97, 99, 100, 104, 109, 113, 127, 128, 139, 149, 151, 169, 179, 239
Offset: 1

Views

Author

Gheorghe Coserea, Oct 22 2016

Keywords

Crossrefs

Cf. A276183.

Programs

  • PARI
    A000003(n) = qfbclassno(-4*n);
    A000089(n) = {
      if (n%4 == 0 || n%4 == 3, return(0));
      if (n%2 == 0, n \= 2);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 4 == 3, 0, 2));
    };
    A000086(n) = {
      if (n%9 == 0 || n%3 == 2, return(0));
      if (n%3 == 0, n \= 3);
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, if (f[k, 1] % 3 == 2, 0, 2));
    };
    A001615(n) = {
      my(f = factor(n), fsz = matsize(f)[1],
         g = prod(k=1, fsz, (f[k, 1]+1)),
         h = prod(k=1, fsz, f[k, 1]));
      return((n*g)\h);
    };
    A001616(n) = {
      my(f = factor(n), fsz = matsize(f)[1]);
      prod(k = 1, fsz, f[k, 1]^(f[k, 2]\2) + f[k, 1]^((f[k, 2]-1)\2));
    };
    A001617(n) = 1 + A001615(n)/12 - A000089(n)/4 - A000086(n)/3 - A001616(n)/2;
    A276183(n) = {
      my(r = if (n%8 == 3, 4, n%8 == 7, 6, 3));
      if (n < 5, 0, (1 + A001617(n))/2 -  r * A000003(n)/12);
    };
    Vec(select(x->x==3, vector(500, n, A276183(n)), 1))
Previous Showing 31-34 of 34 results.