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 1-10 of 19 results. Next

A316905 a(n) is the index of the first occurrence of n in A316774.

Original entry on oeis.org

0, 1, 2, 5, 4, 8, 11, 22, 14, 32, 28, 42, 48, 45, 68, 71, 77, 89, 108, 115, 92, 140, 95, 149, 216, 268, 194, 260, 310, 254, 263, 340, 362, 257, 295, 277, 298, 476, 346, 431, 365, 560, 539, 424, 486, 462, 576, 479, 579, 692, 657, 707, 754, 794, 757, 797, 928
Offset: 0

Views

Author

Alois P. Heinz, Jul 18 2018

Keywords

Examples

			a(4) = 4 because A316774(j) = 4 for j in {4,7,12,13,36,49,55} with minimal element 4.
		

Crossrefs

Cf. A316774, A316973, A316984, A330440 (a sorted version of this), A330447, A330448.

Programs

  • Maple
    b:= proc() 0 end:
    g:= proc(n) option remember; local t;
          t:= `if`(n<2, n, b(g(n-1))+b(g(n-2)));
          b(t):= b(t)+1; t
        end:
    a:= proc() local t, a; t, a:= -1, proc() -1 end;
          proc(n) local h;
            while a(n) = -1 do
              t:= t+1; h:= g(t);
              if a(h) = -1 then a(h):= t fi
            od; a(n)
          end
        end():
    seq(a(n), n=0..100);
  • Mathematica
    b[_] = 0;
    g[n_] := g[n] = Module[{t}, t = If[n < 2, n, b[g[n - 1]] + b[g[n - 2]]];       b[t] = b[t] + 1; t];
    a[n_] := Module[{t = -1, a}, a[_] = -1; Module[{h}, While[a[n] == -1, t = t + 1; h = g[t]; If[a[h] == -1, a[h] = t]]; a[n]]];
    Table[a[n], {n, 0, 100}] (* Jean-François Alcover, Aug 28 2023, after Alois P. Heinz *)

Formula

a(n) = min { j >= 0 : A316774(j) = n }.

A316973 a(n) is the number of occurrences of n in A316774.

Original entry on oeis.org

1, 1, 3, 4, 7, 7, 15, 12, 18, 16, 25, 23, 14, 22, 26, 33, 23, 38, 32, 35, 45, 49, 41, 44, 58, 49, 59, 39, 49, 69, 54, 57, 57, 75, 79, 62, 75, 76, 74, 81, 75, 78, 74, 90, 86, 86, 88, 78, 78, 105, 106, 109, 129, 91, 92, 111, 108, 101, 126, 130, 116, 129, 133, 140
Offset: 0

Views

Author

Alois P. Heinz, Jul 17 2018

Keywords

Comments

These values may be only conjectural, in which case the b-file should be changed to an a-file and marked as conjectured. - N. J. A. Sloane, Dec 14 2019

Examples

			a(4) = 7 because A316774(j) = 4 for j in s = {4,7,12,13,36,49,55} and |s| = 7.
		

Crossrefs

Formula

a(n) = |{ j : A316774(j) = n }|.

A316984 a(n) is the index of the last occurrence of n in A316774.

Original entry on oeis.org

0, 1, 6, 16, 55, 488, 314, 367, 279, 562, 519, 799, 500, 694, 792, 876, 1322, 1598, 5826, 1814, 6102, 5345, 2042, 5105, 2949, 3288, 5260, 4971, 6353, 5172, 8596, 3193, 6528, 8065, 8194, 6538, 6881, 6966, 7963, 5993, 8114, 9090, 8457, 8948, 12703, 9994, 6568
Offset: 0

Views

Author

Alois P. Heinz, Jul 18 2018

Keywords

Comments

[It may be that these values are only conjectural. If so, the b-file should be changed to an a-file and marked as conjectured. - N. J. A. Sloane, Dec 14 2019]

Examples

			a(4) = 55 because A316774(j) = 4 for j in {4,7,12,13,36,49,55} with maximal element 55.
		

Crossrefs

Formula

a(n) = max { j >= 0 : A316774(j) = n }.

A330439 Number of times g(n) appears in [g(0),g(1),...,g(n)], where g = A316774.

Original entry on oeis.org

1, 1, 1, 2, 1, 1, 3, 2, 1, 2, 3, 1, 3, 4, 1, 2, 4, 2, 3, 4, 2, 5, 1, 6, 2, 3, 3, 7, 1, 4, 4, 5, 1, 8, 2, 2, 5, 3, 6, 3, 4, 7, 1, 8, 5, 1, 9, 3, 1, 6, 4, 4, 9, 2, 2, 7, 6, 3, 7, 5, 2, 5, 6, 3, 8, 3, 4, 10, 1, 5, 10, 1, 6, 7, 4, 7, 8, 1, 9, 6, 2, 11, 5, 2, 8, 7, 3, 8, 9, 1, 9, 10, 1, 10, 11, 1, 4, 5, 10, 4, 2, 11, 6
Offset: 0

Views

Author

Alois P. Heinz, Dec 14 2019

Keywords

Crossrefs

Programs

  • Maple
    b:= proc() 0 end:
    g:= proc(n) option remember; local t;
          t:= `if`(n<2, n, b(g(n-1))+b(g(n-2)));
          b(t):= b(t)+1; t
        end:
    a:= proc(n) option remember; b(g(n)) end:
    seq(a(n), n=0..200);
  • Mathematica
    b[_] = 0;
    g[n_] := g[n] = Module[{t},
         t = If[n<2, n, b[g[n-1]]+b[g[n-2]]];
         b[t]++; t];
    a[n_] := a[n] = b[g[n]];
    a /@ Range[0, 200] (* Jean-François Alcover, Mar 30 2021, after Alois P. Heinz *)

A330440 Numbers k such that A316774(k) != A316774(j) for all 0 <= j < k.

Original entry on oeis.org

0, 1, 2, 4, 5, 8, 11, 14, 22, 28, 32, 42, 45, 48, 68, 71, 77, 89, 92, 95, 108, 115, 140, 149, 194, 216, 254, 257, 260, 263, 268, 277, 295, 298, 310, 340, 346, 362, 365, 424, 431, 462, 476, 479, 486, 539, 560, 576, 579, 657, 692, 707, 754, 757, 794, 797, 928
Offset: 1

Views

Author

Alois P. Heinz, Dec 14 2019

Keywords

Comments

This is a sorted version of A316905.
List of indices k such that A330439(k) = 1.

Crossrefs

Column k=1 of A330587.

Programs

  • Maple
    b:= proc() 0 end:
    g:= proc(n) option remember; local t;
          t:= `if`(n<2, n, b(g(n-1))+b(g(n-2)));
          b(t):= b(t)+1; t
        end:
    f:= proc(n) option remember; b(g(n)) end:
    a:= proc(n) option remember; local k; for k from 1+
          `if`(n=1, -1, a(n-1)) while f(k)<>1 do od; k
        end:
    seq(a(n), n=1..80);
  • Mathematica
    b[_] = 0;
    g[n_] := g[n] = Module[{t},
         t = If[n < 2, n, b[g[n - 1]] + b[g[n - 2]]];
         b[t]++; t];
    f[n_] := f[n] = b[g[n]];
    a[n_] := a[n] = Module[{k}, For[k = 1 +
         If[n == 1, -1, a[n - 1]], f[k] != 1, k++]; k];
    Table[a[n], {n, 1, 80}] (* Jean-François Alcover, Jun 01 2022, after Alois P. Heinz *)

Formula

{ k >= 0 : A330439(k) = 1 }.

A330330 Record high points in A316774.

Original entry on oeis.org

0, 1, 2, 4, 5, 6, 8, 10, 11, 13, 14, 15, 16, 17, 20, 22, 23, 26, 29, 33, 35, 36, 38, 40, 43, 45, 47, 48, 50, 51, 52, 54, 55, 56, 58, 60, 62, 65, 66, 71, 72, 73, 74, 75, 77, 78, 80, 81, 83, 84, 91, 98, 102, 111, 112, 118, 120, 124, 131, 136, 139, 144, 145, 147, 149, 152, 156, 159, 160, 163
Offset: 1

Views

Author

N. J. A. Sloane, Dec 14 2019

Keywords

Crossrefs

A330331 Positions of records in A316774.

Original entry on oeis.org

0, 1, 2, 4, 8, 11, 14, 28, 42, 45, 68, 71, 77, 89, 92, 95, 149, 194, 254, 257, 277, 298, 346, 365, 424, 462, 479, 579, 657, 707, 754, 757, 797, 928, 1107, 1110, 1147, 1150, 1295, 1298, 1453, 1456, 1462, 1590, 1593, 1673, 1676, 1819, 1822, 1982, 2095, 2395, 2593, 2665, 2874, 3355, 3724, 3873, 4131, 4359, 4510
Offset: 1

Views

Author

N. J. A. Sloane, Dec 14 2019

Keywords

Crossrefs

A330447 a(n) is the smallest index k such that {0,1,2,...,n} is a subset of { A316774(j) : 0 <= j <= k }.

Original entry on oeis.org

0, 1, 2, 5, 5, 8, 11, 22, 22, 32, 32, 42, 48, 48, 68, 71, 77, 89, 108, 115, 115, 140, 140, 149, 216, 268, 268, 268, 310, 310, 310, 340, 362, 362, 362, 362, 362, 476, 476, 476, 476, 560, 560, 560, 560, 560, 576, 576, 579, 692, 692, 707, 754, 794, 794, 797, 928
Offset: 0

Views

Author

Alois P. Heinz, Dec 15 2019

Keywords

Crossrefs

Programs

  • Maple
    b:= proc() 0 end:
    g:= proc(n) option remember; local t;
          t:= `if`(n<2, n, b(g(n-1))+b(g(n-2)));
          b(t):= b(t)+1; t
        end:
    f:= proc() local t, a; t, a:= -1, proc() -1 end;
          proc(n) local h;
            while a(n) = -1 do
              t:= t+1; h:= g(t);
              if a(h) = -1 then a(h):= t fi
            od; a(n)
          end
        end():
    a:= proc(n) option remember; `if`(n<0, 0,
          max(a(n-1), f(n)))
        end:
    seq(a(n), n=0..100);
  • Mathematica
    b[_] = 0;
    g[n_] := g[n] = Module[{t}, t = If[n < 2, n, b[g[n - 1]] + b[g[n - 2]]]; b[t] = b[t] + 1; t];
    f[n_] := Module[{t, a}, t = -1; a[_] = -1; Module[{h}, While[a[n] == -1, t = t + 1; h = g[t]; If[a[h] == -1, a[h] = t]]; a[n]]];
    a[n_] := a[n] = If[n < 0, 0, Max[a[n - 1], f[n]]];
    Table[a[n], {n, 0, 100}] (* Jean-François Alcover, Oct 13 2022, after Alois P. Heinz *)

Formula

a(n) = max_{0 <= j <= n} A316905(j).
a(n) >= A316905(n).
a(n) <= a(n+1).

A330587 A(n,k) is the n-th index m such that A330439(m) = k; square array A(n,k), n>=1, k>=1, read by antidiagonals.

Original entry on oeis.org

0, 3, 1, 6, 7, 2, 13, 10, 9, 4, 21, 16, 12, 15, 5, 23, 31, 19, 18, 17, 8, 27, 38, 36, 29, 25, 20, 11, 33, 41, 49, 44, 30, 26, 24, 14, 46, 43, 55, 56, 59, 40, 37, 34, 22, 67, 52, 64, 58, 62, 61, 50, 39, 35, 28, 81, 70, 78, 76, 73, 72, 69, 51, 47, 53, 32, 104, 94, 91, 88, 84, 75, 79, 82, 66, 57, 54, 42
Offset: 1

Views

Author

Alois P. Heinz, Dec 18 2019

Keywords

Examples

			Square array A(n,k) begins:
   0,  3,  6, 13,  21,  23,  27,  33,  46,  67, ...
   1,  7, 10, 16,  31,  38,  41,  43,  52,  70, ...
   2,  9, 12, 19,  36,  49,  55,  64,  78,  91, ...
   4, 15, 18, 29,  44,  56,  58,  76,  88,  93, ...
   5, 17, 25, 30,  59,  62,  73,  84,  90,  98, ...
   8, 20, 26, 40,  61,  72,  75,  87, 117, 139, ...
  11, 24, 37, 50,  69,  79,  85, 121, 124, 154, ...
  14, 34, 39, 51,  82, 102, 118, 142, 155, 157, ...
  22, 35, 47, 66,  97, 110, 133, 180, 190, 202, ...
  28, 53, 57, 74, 106, 116, 164, 183, 197, 205, ...
		

Crossrefs

Column k=1 gives A330440.
Row n=1 gives A330588.
Main diagonal gives A330589.

Programs

  • Maple
    b:= proc() 0 end:
    g:= proc(n) option remember; local t;
          t:= `if`(n<2, n, b(g(n-1))+b(g(n-2)));
          b(t):= b(t)+1; t
        end:
    f:= proc(n) option remember; b(g(n)) end:
    A:= proc() local l, t; t, l:= -1, proc() [] end;
          proc(n,k) local h;
            while nops(l(k))
    				
  • Mathematica
    b[_] = 0;
    g[n_] := g[n] = Module[{t}, t = If[n < 2, n, b[g[n - 1]] + b[g[n - 2]]]; b[t]++; t];
    f[n_] := f[n] = b[g[n]];
    A[n_, k_] := Module[{l, t = -1, h}, l[_] = {}; While[Length[l[k]] < n, t++; h = f[t]; AppendTo[l[h], t]]; l[k][[n]]];
    Table[Table[A[n, 1 + d - n], {n, 1, d}], {d, 1, 14}] // Flatten (* Jean-François Alcover, Feb 11 2021, after Alois P. Heinz *)

A317223 a(0) = 0, a(1) = 1; for n >= 2, a(n) = freq(a(freq(a(n-1),n)),n) where freq(i, j) is the number of times i appears in the terms a(0) .. a(j-1).

Original entry on oeis.org

0, 1, 1, 2, 2, 2, 3, 2, 4, 2, 5, 2, 1, 6, 3, 3, 6, 3, 6, 6, 6, 6, 4, 3, 6, 6, 2, 7, 3, 6, 7, 3, 7, 7, 7, 7, 7, 7, 2, 2, 9, 3, 2, 1, 10, 4, 10, 4, 10, 10, 10, 10, 8, 4, 10, 10, 5, 4, 8, 4, 10, 10, 2, 11, 4, 8, 11, 4, 11, 11, 11, 11, 8, 11, 11, 9, 4, 2, 4, 12, 4, 4, 9, 12, 4, 8, 12, 12, 12, 12, 8, 8, 12, 12, 14, 4, 8
Offset: 0

Views

Author

Altug Alkan, Jul 24 2018

Keywords

Crossrefs

Programs

  • Maple
    b:= proc() 0 end:
    a:= proc(n) option remember; local t;
          t:= `if`(n<2, n, b(a(b(a(n-1)))));
          b(t):= b(t)+1; t
        end:
    seq(a(n), n=0..200);  # Alois P. Heinz, Jul 24 2018
  • Mathematica
    b[_] = 0;
    a[n_] := a[n] = Module[{t}, t = If[n<2, n, b[a[b[a[n-1]]]]]; b[t]++; t];
    a /@ Range[0, 200] (* Jean-François Alcover, Nov 09 2020, after Alois P. Heinz *)
Showing 1-10 of 19 results. Next