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.

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A359511 Number of partitions of n into at most 2 positive Fibonacci numbers (with a single type of 1).

Original entry on oeis.org

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

Views

Author

Ilya Gutkovskiy, Jan 03 2023

Keywords

Crossrefs

Formula

a(n) = Sum_{k=0..2} A319394(n,k). - Alois P. Heinz, Jan 03 2023

A359512 Number of partitions of n into at most 3 positive Fibonacci numbers (with a single type of 1).

Original entry on oeis.org

1, 1, 2, 3, 3, 4, 4, 4, 4, 4, 4, 4, 3, 4, 3, 4, 4, 3, 4, 3, 1, 4, 2, 4, 4, 2, 4, 3, 2, 4, 1, 3, 1, 0, 4, 2, 3, 4, 2, 4, 2, 1, 4, 2, 3, 2, 0, 4, 1, 1, 3, 0, 1, 0, 0, 4, 2, 3, 3, 2, 4, 2, 1, 4, 1, 2, 1, 0, 4, 2, 2, 3, 0, 2, 0, 0, 4, 1, 1, 1, 0, 3, 0, 0, 1, 0, 0, 0, 0, 4, 2, 3, 3
Offset: 0

Views

Author

Ilya Gutkovskiy, Jan 03 2023

Keywords

Crossrefs

Formula

a(n) = Sum_{k=0..3} A319394(n,k). - Alois P. Heinz, Jan 03 2023

A028290 Expansion of 1/((1-x)(1-x^2)(1-x^3)(1-x^5)(1-x^8)).

Original entry on oeis.org

1, 1, 2, 3, 4, 6, 8, 10, 14, 17, 22, 27, 33, 40, 48, 57, 68, 79, 93, 107, 124, 142, 162, 184, 209, 235, 265, 296, 331, 368, 409, 452, 500, 550, 605, 663, 726, 792, 864, 939, 1021, 1106, 1198, 1294, 1397, 1505
Offset: 0

Views

Author

Keywords

Comments

Number of partitions of n into parts equal to 1, 2, 3, 5 and 8. E.g. a(5)=6 because we have 5, 3+2, 3+1+1, 2+2+1, 2+1+1+1 and 1+1+1+1+1. - Emeric Deutsch, Mar 25 2005

Crossrefs

Programs

  • Haskell
    import Data.MemoCombinators (memo2, integral)
    a028290 n = a028290_list !! n
    a028290_list = map (p' 0) [0..] where
       p' = memo2 integral integral p
       p _ 0 = 1
       p 5 _ = 0
       p k m | m < parts !! k = 0
             | otherwise = p' k (m - parts !! k) + p' (k + 1) m
       parts = [1, 2, 3, 5, 8]
    -- Reinhard Zumkeller, Dec 09 2015
  • Maple
    G:=1/(1-x)/(1-x^2)/(1-x^3)/(1-x^5)/(1-x^8): Gser:=series(G,x=0,47): 1, seq(coeff(Gser,x^n),n=1..45); # Emeric Deutsch, Mar 25 2005
  • Mathematica
    CoefficientList[ Series[ 1/Product[1 - x^Fibonacci[i], {i, 2, 6}], {x, 0, 45}], x] (* Robert G. Wilson v, Oct 15 2016 *)
    CoefficientList[Series[1/((1-x)(1-x^2)(1-x^3)(1-x^5)(1-x^8)),{x,0,100}],x] (* Harvey P. Dale, Jan 26 2019 *)
  • PARI
    Vec(1/((1-x)*(1-x^2)*(1-x^3)*(1-x^5)*(1-x^8))+O(x^99)) \\ Charles R Greathouse IV, Sep 27 2012
    

A239001 Irregular triangular array read by rows: row n gives a list of the partitions of n into Fibonacci numbers.

Original entry on oeis.org

1, 2, 1, 1, 3, 2, 1, 1, 1, 1, 3, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 5, 3, 2, 3, 1, 1, 2, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 3, 3, 3, 2, 1, 3, 1, 1, 1, 2, 2, 2, 2, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 2, 5, 1, 1, 3, 3, 1, 3, 2, 2, 3, 2, 1, 1, 3, 1, 1
Offset: 1

Views

Author

Clark Kimberling, Mar 08 2014

Keywords

Comments

The number of partitions represented in row n is A003107(n).
The parts of a partition are nonincreasing and the order of the partitions is anti-lexicographic. As parts one uses A000045(n), n >= 2. - Wolfdieter Lang, Mar 17 2014

Examples

			1
2 1 1
3 2 1 1 1 1
3 1 2 2 2 1 1 1 1 1 1
5 3 2 3 1 1 2 2 1 2 1 1 1 1 1 1 1 1
Row 5 represents these six partitions: 5, 32, 311, 221, 2111, 11111.
From _Wolfdieter Lang_, Mar 17 2014: (Start)
The array with separated partitions begins:
n\k   1      2      3        4        5          6          7            8             9             10 ...
1:    1
2:    2    1,1
3:    3    2,1  1,1,1
4:  3,1    2,2  2,1,1  1,1,1,1
5:    5    3,2  3,1,1    2,2,1  2,1,1,1  1,1,1,1,1
6:  5,1    3,3  3,2,1  3,1,1,1    2,2,2    2,2,1,1  2,1,1,1,1  1,1,1,1,1,1
7:  5,2  5,1,1  3,3,1    3,2,2  3,2,1,1  3,1,1,1,1    2,2,2,1    2,2,1,1,1   2,1,1,1,1,1  1,1,1,1,1,1,1
...
Row n=8: 8  5,3  5,2,1  5,1,1,1  3,3,2  3,3,1,1  3,2,2,1  3,2,1,1,1  3,1,1,1,1,1   2,2,2,2   2,2,2,1,1
  2,2,1,1,1,1  2,1,1,1,1,1,1  1,1,1,1,1,1,1,1;
Row n=9  8,1  5,3,1  5,2,2   5,2,1,1   5,1,1,1,1  3,3,3   3,3,2,1   3,3,1,1,1  3,2,2,2  3,2,2,1,1
3,2,1,1,1,1   3,1,1,1,1,1,1  2,2,2,2,1  2,2,2,1,1,1  2,2,1,1,1,1,1   2,1,1,1,1,1,1,1   1,1,1,1,1,1,1,1,1;
Row n=10: 8,2  8,1,1   5,5   5,3,2  5,3,1,1  5,2,2,1  5,2,1,1,1  5,1,1,1,1,1   3,3,3,1  3,3,2,2  3,3,2,1,1
  3,3,1,1,1,1   3,2,2,2,1  3,2,2,1,1,1   3,2,1,1,1,1,1   3,1,1,1,1,1,1,1   2,2,2,2,2   2,2,2,2,1,1
  2,2,2,1,1,1,1  2,2,1,1,1,1,1,1  2,1,1,1,1,1,1,1,1  1,1,1,1,1,1,1,1,1,1.
-----------------------------------------------------------------------------------------------------------
(End)
		

Crossrefs

Programs

  • Mathematica
    f = Table[Fibonacci[n], {n, 2, 60}]; p[n_, k_] := p[n, k] = IntegerPartitions[n][[k]]; s[n_, k_] := If[Union[f, DeleteDuplicates[p[n, k]]] == f, p[n, k], 0]; t[n_] := Table[s[n, k], {k, 1, PartitionsP[n]}]; TableForm[Table[DeleteCases[t[n], 0], {n, 1, 12}]] (* shows partitions *)
    y = Flatten[Table[DeleteCases[t[n], 0], {n, 1, 12}]] (* A239001 *)
    (* also *)
    FibonacciQ[n_] := IntegerQ[Sqrt[5 n^2 + 4]] || IntegerQ[Sqrt[5 n^2 - 4]]; Attributes[FibonacciQ] = {Listable}; TableForm[t = Map[Select[IntegerPartitions[#], And @@ FibonacciQ[#] &] &, Range[0, 12]]]
    Flatten[t] (* Peter J. C. Moses, Mar 24 2014 *)

A238998 Number of partitions of n that such that no part is a Fibonacci number.

Original entry on oeis.org

1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 2, 2, 3, 2, 4, 4, 6, 5, 9, 8, 11, 11, 16, 16, 22, 22, 29, 31, 40, 42, 54, 57, 71, 77, 95, 103, 127, 137, 165, 182, 218, 238, 285, 313, 369, 408, 479, 530, 619, 684, 794, 883, 1019, 1130, 1304, 1446, 1658, 1843, 2107, 2340, 2670
Offset: 0

Views

Author

Clark Kimberling, Mar 08 2014

Keywords

Examples

			a(15) counts these partitions:  [15], [11,4], [9,6], [7,4,4]; a(16) counts these:  [16], [12,4], [10,6], [9,7], [6,6,4], [4,4,4,4].
		

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(add(
          `if`((f-> issqr(f+4) or issqr(f-4))(5*d^2), 0, d),
            d=numtheory[divisors](j))*a(n-j), j=1..n)/n)
        end:
    seq(a(n), n=0..100);  # Alois P. Heinz, Mar 31 2017
  • Mathematica
    p[n_] := IntegerPartitions[n, All, Complement[Range@n, Fibonacci@Range@15]]; Table[p[n], {n, 0, 20}] (* shows partitions *)
    a[n_] := Length@p@n; a /@ Range[0, 80] (* counts partitions *)
    (* Second program: *)
    a[n_] := a[n] = If[n == 0, 1, Sum[Sum[
        If[Function[f, IntegerQ@Sqrt[f+4] || IntegerQ@Sqrt[f-4]][5*d^2], 0, d],
        {d, Divisors[j]}]*a[n - j], {j, 1, n}]/n];
    a /@ Range[0, 100] (* Jean-François Alcover, Jun 05 2021, after Alois P. Heinz *)
  • PARI
    N=66; q='q+O('q^N); Vec( prod(n=1,11,1-q^fibonacci(n+1))/eta(q) ) \\ Joerg Arndt, Mar 11 2014

Formula

G.f.: A(x) = sum(1/product(1 - x^c(i))), i >=1, where c(i) are the non-Fibonacci numbers.

A239000 Number of partitions of n using Fibonacci numbers > 2.

Original entry on oeis.org

1, 0, 0, 1, 0, 1, 1, 0, 2, 1, 1, 2, 1, 3, 2, 2, 4, 2, 4, 4, 3, 7, 4, 5, 8, 5, 9, 8, 7, 12, 9, 11, 13, 11, 17, 14, 15, 20, 16, 22, 22, 20, 29, 24, 27, 33, 28, 37, 36, 35, 45, 40, 46, 50, 47, 60, 55, 58, 69, 62, 75, 76, 73, 91, 84, 91, 102, 95, 114, 112, 113
Offset: 0

Views

Author

Clark Kimberling, Mar 08 2014

Keywords

Examples

			a(21) counts these partitions: [21], [13,8], [13,5,3], [8,8,5], [8,5,5,3], [5,5,5,3,3], [3,3,3,3,3,3,3].
		

Crossrefs

Programs

  • Mathematica
    p[n_] := IntegerPartitions[n, All, Fibonacci@Range[4, 60]]; Table[p[n], {n, 0, 12}] (*shows partitions*)
    a[n_] := Length@p@n; a /@ Range[0, 80] (*counts partitions, A239000*)
  • PARI
    N=66; q='q+O('q^N); Vec( 1/prod(n=1,11,1-q^fibonacci(n+3)) ) \\ Joerg Arndt, Mar 11 2014

Formula

G.f.: 1/Product_{i>=4} (1 - x^Fibonacci(i)).

A281689 Expansion of Sum_{k>=2} x^Fibonacci(k)/(1 - x^Fibonacci(k)) / Product_{k>=2} (1 - x^Fibonacci(k)).

Original entry on oeis.org

1, 3, 6, 11, 18, 29, 42, 62, 86, 119, 159, 211, 273, 352, 446, 562, 697, 864, 1054, 1284, 1550, 1860, 2220, 2639, 3114, 3669, 4293, 5011, 5823, 6745, 7783, 8956, 10268, 11747, 13390, 15237, 17281, 19561, 22089, 24889, 27979, 31405, 35157, 39309, 43856, 48849, 54319, 60309, 66840, 73992, 81760, 90243
Offset: 1

Views

Author

Ilya Gutkovskiy, Jan 27 2017

Keywords

Comments

Total number of parts in all partitions of n into Fibonacci parts (with a single type of 1).
Convolution of A003107 and A005086.

Examples

			a(5) = 18 because we have [5], [3, 2], [3, 1, 1], [2, 2, 1], [2, 1, 1, 1], [1, 1, 1, 1, 1] and 1 + 2 + 3 + 3 + 4 + 5 = 18.
		

Crossrefs

Programs

  • Maple
    h:= proc(n) option remember; `if`(n<1, 0, `if`((t->
          issqr(t+4) or issqr(t-4))(5*n^2), n, h(n-1)))
        end:
    b:= proc(n, i) option remember; `if`(n=0 or i=1, [1, n],
           b(n, h(i-1))+(p->p+[0, p[1]])(b(n-i, h(min(n-i, i)))))
        end:
    a:= n-> b(n, h(n))[2]:
    seq(a(n), n=1..70);  # Alois P. Heinz, Sep 18 2018
  • Mathematica
    Rest[CoefficientList[Series[Sum[x^Fibonacci[k]/(1 - x^Fibonacci[k]), {k, 2, 20}]/Product[1 - x^Fibonacci[k], {k, 2, 20}], {x, 0, 52}], x]]

Formula

G.f.: Sum_{k>=2} x^Fibonacci(k)/(1 - x^Fibonacci(k)) / Product_{k>=2} (1 - x^Fibonacci(k)).
a(n) = Sum_{k=1..n} k * A319394(n,k). - Alois P. Heinz, Sep 18 2018

A290807 Number of partitions of n into Pell parts (A000129).

Original entry on oeis.org

1, 1, 2, 2, 3, 4, 5, 6, 7, 8, 10, 11, 14, 15, 18, 20, 23, 26, 29, 32, 36, 39, 44, 47, 53, 57, 63, 68, 74, 81, 88, 95, 103, 110, 120, 128, 139, 148, 159, 170, 182, 195, 208, 221, 236, 250, 267, 282, 300, 317, 336, 355, 375, 396, 418, 440, 464, 487, 514, 539, 568, 595, 625, 655, 687, 720, 754, 788
Offset: 0

Views

Author

Ilya Gutkovskiy, Aug 11 2017

Keywords

Examples

			a(5) = 4 because we have [5], [2, 2, 1], [2, 1, 1, 1] and [1, 1, 1, 1, 1].
		

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[Product[1/(1 - x^Fibonacci[k, 2]), {k, 1, 15}], {x, 0, 67}], x]

Formula

G.f.: Product_{k>=1} 1/(1 - x^A000129(k)).

A357452 Number of partitions of n into tetranacci numbers 1,2,4,8,15,29, ... (A000078).

Original entry on oeis.org

1, 1, 2, 2, 4, 4, 6, 6, 10, 10, 14, 14, 20, 20, 26, 27, 36, 37, 46, 48, 60, 62, 74, 78, 94, 98, 114, 120, 140, 147, 168, 178, 204, 215, 242, 256, 288, 304, 338, 358, 398, 420, 462, 488, 537, 567, 619, 654, 714, 753, 816, 860, 932, 982, 1058, 1114
Offset: 0

Views

Author

Ilya Gutkovskiy, Sep 29 2022

Keywords

Crossrefs

Programs

Formula

G.f.: Product_{k>=4} 1 / (1 - x^A000078(k)).

A357454 Number of partitions of n into pentanacci numbers 1,2,4,8,16,31, ... (A001591).

Original entry on oeis.org

1, 1, 2, 2, 4, 4, 6, 6, 10, 10, 14, 14, 20, 20, 26, 26, 36, 36, 46, 46, 60, 60, 74, 74, 94, 94, 114, 114, 140, 140, 166, 167, 202, 203, 238, 240, 284, 286, 330, 334, 390, 394, 450, 456, 524, 530, 598, 608, 692, 702, 786, 800, 900, 914, 1014, 1034
Offset: 0

Views

Author

Ilya Gutkovskiy, Sep 29 2022

Keywords

Crossrefs

Programs

Formula

G.f.: Product_{k>=5} 1 / (1 - x^A001591(k)).
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