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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A332277 Number of widely totally normal integer partitions of n.

Original entry on oeis.org

1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 4, 4, 2, 4, 4, 6, 3, 5, 7, 6, 8, 12, 9, 12, 13, 11, 12, 18, 17, 12, 32, 19, 25, 33, 30, 28, 44, 33, 43, 57, 51, 60, 83, 70, 83, 103, 96, 97, 125, 117, 134, 157, 157, 171, 226, 215, 238, 278, 302, 312, 359, 357, 396, 450, 444, 477, 580
Offset: 0

Views

Author

Gus Wiseman, Feb 12 2020

Keywords

Comments

A sequence is widely totally normal if either it is all 1's (wide) or it covers an initial interval of positive integers (normal) and has widely totally normal run-lengths.
Also the number of widely totally normal reversed integer partitions of n.

Examples

			The a(n) partitions for n = 1, 4, 10, 11, 16, 18:
  1  211   4321        33221        443221            543321
     1111  33211       322211       4432111           4333221
           322111      332111       1111111111111111  4432221
           1111111111  11111111111                    4433211
                                                      43322211
                                                      44322111
                                                      111111111111111111
		

Crossrefs

Normal partitions are A000009.
Taking multiplicities instead of run-lengths gives A317245.
Constantly recursively normal partitions are A332272.
The Heinz numbers of these partitions are A332276.
The case of all compositions (not just partitions) is A332279.
The co-strong version is A332278.
The recursive version is A332295.
The narrow version is a(n) + 1 for n > 1.

Programs

  • Mathematica
    recnQ[ptn_]:=Or[ptn=={},Union[ptn]=={1},And[Union[ptn]==Range[Max[ptn]],recnQ[Length/@Split[ptn]]]];
    Table[Length[Select[IntegerPartitions[n],recnQ]],{n,0,30}]

Extensions

a(61)-a(66) from Jinyuan Wang, Jun 26 2020

A317088 Number of normal integer partitions of n whose multiset of multiplicities is also normal.

Original entry on oeis.org

1, 1, 0, 1, 1, 1, 1, 1, 1, 2, 3, 4, 1, 4, 4, 5, 4, 6, 7, 9, 10, 13, 13, 15, 15, 17, 23, 22, 29, 29, 34, 36, 47, 45, 59, 60, 72, 77, 93, 95, 112, 121, 129, 149, 169, 176, 202, 228, 247, 268, 305, 334, 372, 405, 452, 496, 544, 594, 663, 724, 802
Offset: 0

Views

Author

Gus Wiseman, Jul 21 2018

Keywords

Comments

A multiset is normal if it spans an initial interval of positive integers.

Examples

			The a(18) = 7 integer partitions are (543321), (5432211), (4433211), (4432221), (44322111), (4333221), (43322211).
		

Crossrefs

Programs

  • Mathematica
    normalQ[m_]:=Union[m]==Range[Max[m]];
    Table[Length[Select[IntegerPartitions[n],And[normalQ[#],normalQ[Length/@Split[#]]]&]],{n,30}]
  • Python
    from sympy.utilities.iterables import partitions
    from sympy import integer_nthroot
    def A317088(n):
        if n == 0:
            return 1
        c = 0
        for d in partitions(n,k=integer_nthroot(2*n,2)[0]):
            l = len(d)
            if l > 0 and l == max(d):
                v = set(d.values())
                if len(v) == max(v):
                    c += 1
        return c # Chai Wah Wu, Jun 23 2020

A332297 Number of narrowly totally strongly normal integer partitions of n.

Original entry on oeis.org

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

Views

Author

Gus Wiseman, Feb 15 2020

Keywords

Comments

A partition is narrowly totally strongly normal if either it is empty, a singleton (narrow), or it covers an initial interval of positive integers (normal) and has weakly decreasing run-lengths (strong) that are themselves a narrowly totally strongly normal partition.

Examples

			The a(1) = 1, a(2) = 2, a(3) = 3, and a(55) = 4 partitions:
  (1)  (2)    (3)      (55)
       (1,1)  (2,1)    (10,9,8,7,6,5,4,3,2,1)
              (1,1,1)  (5,5,5,5,5,4,4,4,4,3,3,3,2,2,1)
                       (1)^55
For example, starting with the partition (3,3,2,2,1) and repeatedly taking run-lengths gives (3,3,2,2,1) -> (2,2,1) -> (2,1) -> (1,1) -> (2). The first four are normal and have weakly decreasing run-lengths, and the last is a singleton, so (3,3,2,2,1) is counted under a(11).
		

Crossrefs

Normal partitions are A000009.
The non-totally normal version is A316496.
The widely alternating version is A332292.
The non-strong case of compositions is A332296.
The case of compositions is A332336.
The wide version is a(n) - 1 for n > 1.

Programs

  • Mathematica
    tinQ[q_]:=Or[q=={},Length[q]==1,And[Union[q]==Range[Max[q]],GreaterEqual@@Length/@Split[q],tinQ[Length/@Split[q]]]];
    Table[Length[Select[IntegerPartitions[n],tinQ]],{n,0,30}]

Extensions

a(60)-a(80) from Jinyuan Wang, Jun 26 2020

A332289 Number of widely alternately co-strongly normal integer partitions of n.

Original entry on oeis.org

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

Views

Author

Gus Wiseman, Feb 13 2020

Keywords

Comments

An integer partition is widely alternately co-strongly normal if either it is all 1's (wide) or it covers an initial interval of positive integers (normal) and has weakly increasing run-lengths (co-strong) which, if reversed, are themselves a widely alternately co-strongly normal partition.

Examples

			The a(1) = 1, a(3) = 2, and a(10) = 3 partitions:
  (1)  (21)   (4321)
       (111)  (322111)
              (1111111111)
For example, starting with y = (4,3,2,2,1,1,1) and repeatedly taking run-lengths and reversing gives y -> (3,2,1,1) -> (2,1,1) -> (2,1) -> (1,1). These are all normal, have weakly increasing run-lengths, and the last is all 1's, so y is counted a(14).
		

Crossrefs

Normal partitions are A000009.
Dominated by A317245.
The non-co-strong version is A332277.
The total (instead of alternate) version is A332278.
The Heinz numbers of these partitions are A332290.
The strong version is A332292.
The case of reversed partitions is (also) A332292.
The generalization to compositions is A332340.

Programs

  • Mathematica
    totnQ[ptn_]:=Or[ptn=={},Union[ptn]=={1},And[Union[ptn]==Range[Max[ptn]],LessEqual@@Length/@Split[ptn],totnQ[Reverse[Length/@Split[ptn]]]]];
    Table[Length[Select[IntegerPartitions[n],totnQ]],{n,0,30}]

A381435 Numbers appearing more than once in A381431 (section-sum partition of prime indices).

Original entry on oeis.org

5, 7, 11, 13, 17, 19, 23, 25, 26, 29, 31, 34, 37, 38, 39, 41, 43, 46, 47, 49, 51, 52, 53, 57, 58, 59, 61, 62, 65, 67, 68, 69, 71, 73, 74, 76, 79, 82, 83, 85, 86, 87, 89, 91, 92, 93, 94, 95, 97, 101, 103, 104, 106, 107, 109, 111, 113, 115, 116, 117, 118, 119
Offset: 1

Views

Author

Gus Wiseman, Feb 27 2025

Keywords

Comments

The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
The section-sum partition (A381436) of a multiset or partition y is defined as follows: (1) determine and remember the sum of all distinct parts, (2) remove one instance of each distinct part, (3) repeat until no parts are left. The remembered values comprise the section-sum partition. For example, starting with (3,2,2,1,1) we get (6,3).
Equivalently, the k-th part of the section-sum partition is the sum of all (distinct) parts that appear at least k times. Compare to the definition of the conjugate of a partition, where we count parts >= k.
The conjugate of a section-sum partition is a Look-and-Say partition; see A048767, union A351294, count A239455.

Examples

			The terms together with their prime indices begin:
   5: {3}
   7: {4}
  11: {5}
  13: {6}
  17: {7}
  19: {8}
  23: {9}
  25: {3,3}
  26: {1,6}
  29: {10}
  31: {11}
  34: {1,7}
  37: {12}
  38: {1,8}
  39: {2,6}
  41: {13}
  43: {14}
  46: {1,9}
  47: {15}
  49: {4,4}
  51: {2,7}
  52: {1,1,6}
		

Crossrefs

- fixed points are A000961, A000005
- conjugate is A048767, fixed points A048768, A217605
- all numbers present are A381432, conjugate A351294
- numbers missing are A381433, conjugate A351295
- numbers appearing only once are A381434, conjugate A381540
- numbers appearing more than once are A381435 (this), conjugate A381541
A000040 lists the primes, differences A001223.
A055396 gives least prime index, greatest A061395.
A056239 adds up prime indices, row sums of A112798, counted by A001222.
A122111 represents conjugation in terms of Heinz numbers.
A239455 counts section-sum partitions, complement A351293.
A381436 lists section-sum partition of prime indices, conjugate A381440.
Set multipartitions: A050320, A089259, A116540, A296119, A318360, A318361.
Partition ideals: A300383, A317141, A381078, A381441, A381452, A381454.

Programs

  • Mathematica
    prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
    egs[y_]:=If[y=={},{},Table[Total[Select[Union[y],Count[y,#]>=i&]],{i,Max@@Length/@Split[y]}]];
    Select[Range[100],Count[Times@@Prime/@#&/@egs/@IntegerPartitions[Total[prix[#]]],#]>1&]

Formula

The complement is A381434 U A381433.

A381434 Numbers appearing only once in A381431 (section-sum partition of prime indices).

Original entry on oeis.org

1, 2, 3, 4, 8, 9, 10, 14, 15, 16, 20, 22, 27, 28, 32, 33, 35, 40, 44, 45, 50, 55, 56, 64, 75, 77, 80, 81, 88, 98, 99, 100, 112, 128, 130, 135, 160, 170, 175, 176, 182, 190, 195, 196, 200
Offset: 1

Views

Author

Gus Wiseman, Feb 27 2025

Keywords

Comments

The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
The section-sum partition (A381436) of a multiset or partition y is defined as follows: (1) determine and remember the sum of all distinct parts, (2) remove one instance of each distinct part, (3) repeat until no parts are left. The remembered values comprise the section-sum partition. For example, starting with (3,2,2,1,1) we get (6,3).
Equivalently, the k-th part of the section-sum partition is the sum of all (distinct) parts that appear at least k times. Compare to the definition of the conjugate of a partition, where we count parts >= k.
The conjugate of a section-sum partition is a Look-and-Say partition; see A048767, union A351294, count A239455.

Examples

			The terms together with their prime indices begin:
    1: {}
    2: {1}
    3: {2}
    4: {1,1}
    8: {1,1,1}
    9: {2,2}
   10: {1,3}
   14: {1,4}
   15: {2,3}
   16: {1,1,1,1}
   20: {1,1,3}
   22: {1,5}
   27: {2,2,2}
   28: {1,1,4}
   32: {1,1,1,1,1}
		

Crossrefs

- fixed points are A000961, A000005
- conjugate is A048767, fixed points A048768, A217605
- all numbers present are A381432, conjugate A351294
- numbers missing are A381433, conjugate A351295
- numbers appearing only once are A381434 (this), conjugate A381540
- numbers appearing more than once are A381435, conjugate A381541
A000040 lists the primes, differences A001223.
A055396 gives least prime index, greatest A061395.
A056239 adds up prime indices, row sums of A112798, counted by A001222.
A122111 represents conjugation in terms of Heinz numbers.
A239455 counts section-sum partitions, complement A351293.
A381436 lists section-sum partition of prime indices, conjugate A381440.
Set multipartitions: A050320, A089259, A116540, A296119, A318360, A318361.
Partition ideals: A300383, A317141, A381078, A381441, A381452, A381454.

Programs

  • Mathematica
    prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
    egs[y_]:=If[y=={},{},Table[Total[Select[Union[y],Count[y,#]>=i&]],{i,Max@@Length/@Split[y]}]];
    Select[Range[100],Count[Times@@Prime/@#&/@egs/@IntegerPartitions[Total[prix[#]]],#]==1&]

Formula

The complement is A381433 U A381435.

A332276 Heinz numbers of widely totally normal integer partitions.

Original entry on oeis.org

1, 2, 4, 6, 8, 12, 16, 18, 30, 32, 60, 64, 90, 128, 150, 180, 210, 256, 300, 360, 450, 512, 540, 600, 630, 1024, 1050, 1350, 1500, 2048, 2100, 2250, 2310, 2520, 2940, 3150, 3780, 4096, 4200, 4410, 5880, 8192, 8820, 9450, 10500, 11550, 12600, 13230, 14700
Offset: 1

Views

Author

Gus Wiseman, Feb 12 2020

Keywords

Comments

First differs from A317246 in having 630.
A sequence of positive integers is widely totally normal if either it is all 1's (wide) or it covers an initial interval of positive integers (normal) and has widely totally normal run-lengths.
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).

Examples

			The sequence of terms together with their prime indices begins:
    1: {}
    2: {1}
    4: {1,1}
    6: {1,2}
    8: {1,1,1}
   12: {1,1,2}
   16: {1,1,1,1}
   18: {1,2,2}
   30: {1,2,3}
   32: {1,1,1,1,1}
   60: {1,1,2,3}
   64: {1,1,1,1,1,1}
   90: {1,2,2,3}
  128: {1,1,1,1,1,1,1}
  150: {1,2,3,3}
  180: {1,1,2,2,3}
  210: {1,2,3,4}
  256: {1,1,1,1,1,1,1,1}
  300: {1,1,2,3,3}
  360: {1,1,1,2,2,3}
For example, starting with (4,3,2,2,1), the partition with Heinz number 630, and repeatedly taking run-lengths gives (4,3,2,2,1) -> (1,1,2,1) -> (2,1,1) -> (1,2) -> (1,1). These are all normal and the last is all 1's, so 630 belongs to the sequence.
		

Crossrefs

Contains all powers of two A000079 and the primorials A002110.
Heinz numbers of normal integer partitions are A055932.
The case of reversed integer partitions is A332276 (this sequence).
The enumeration of these partitions by sum is A332277.
The enumeration of the generalization to compositions is A332279.
The co-strong version is A332290.
The strong version is A332291.

Programs

  • Mathematica
    primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
    gnaQ[y_]:=Or[y=={},Union[y]=={1},And[Union[y]==Range[Max[y]],gnaQ[Length/@Split[y]]]];
    Select[Range[1000],gnaQ[primeMS[#]]&]

A332296 Number of narrowly totally normal compositions of n.

Original entry on oeis.org

1, 1, 2, 4, 5, 7, 13, 23, 30, 63, 120, 209, 369, 651, 1198, 2174, 3896, 7023, 12699, 22941, 41565
Offset: 0

Views

Author

Gus Wiseman, Feb 15 2020

Keywords

Comments

A sequence is narrowly totally normal if either it is empty, a singleton (narrow), or it covers an initial interval of positive integers (normal) with narrowly totally normal run-lengths.
A composition of n is a finite sequence of positive integers summing to n.

Examples

			The a(0) = 1 through a(6) = 13 compositions:
  ()  (1)  (2)   (3)    (4)     (5)      (6)
           (11)  (12)   (112)   (122)    (123)
                 (21)   (121)   (212)    (132)
                 (111)  (211)   (221)    (213)
                        (1111)  (1121)   (231)
                                (1211)   (312)
                                (11111)  (321)
                                         (1212)
                                         (1221)
                                         (2112)
                                         (2121)
                                         (11211)
                                         (111111)
For example, starting with the composition (1,1,2,3,1,1) and repeatedly taking run-lengths gives (1,1,2,3,1,1) -> (2,1,1,2) -> (1,2,1) -> (1,1,1) -> (3). The first four are normal and the last is a singleton, so (1,1,2,3,1,1) is counted under a(9).
		

Crossrefs

Normal compositions are A107429.
The wide version is A332279.
The wide recursive version (for partitions) is A332295.
The alternating version is A332296 (this sequence).
The strong version is A332336.
The co-strong version is (also) A332336.

Programs

  • Mathematica
    tinQ[q_]:=Or[Length[q]<=1,And[Union[q]==Range[Max[q]],tinQ[Length/@Split[q]]]];
    Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],tinQ]],{n,0,10}]

Formula

For n > 1, a(n) = A332279(n) + 1.

A332336 Number of narrowly totally strongly normal compositions of n.

Original entry on oeis.org

1, 1, 2, 4, 4, 4, 10, 10, 13, 24, 55, 78, 117, 206, 353, 698, 1175, 2014, 3539, 6210, 10831
Offset: 0

Views

Author

Gus Wiseman, Feb 15 2020

Keywords

Comments

A sequence is narrowly totally strongly normal if either it is empty, a singleton (narrow), or it covers an initial interval of positive integers (normal) and has weakly decreasing run-lengths (strong) that are themselves a narrowly totally strongly normal sequence.
A composition of n is a finite sequence of positive integers summing to n.

Examples

			The a(1) = 1 through a(8) = 13 compositions:
  (1)  (2)   (3)    (4)     (5)      (6)       (7)        (8)
       (11)  (12)   (112)   (212)    (123)     (1213)     (1232)
             (21)   (121)   (221)    (132)     (1231)     (2123)
             (111)  (1111)  (11111)  (213)     (1312)     (2132)
                                     (231)     (1321)     (2312)
                                     (312)     (2131)     (2321)
                                     (321)     (3121)     (3212)
                                     (1212)    (11221)    (12131)
                                     (2121)    (12121)    (13121)
                                     (111111)  (1111111)  (21212)
                                                          (22112)
                                                          (111221)
                                                          (11111111)
For example, starting with (22112) and repeated taking run-lengths gives (22112) -> (221) -> (21) -> (11) -> (2). The first four are normal with weakly decreasing run-lengths, and the last is a singleton, so (22112) is counted under a(8).
		

Crossrefs

Normal compositions are A107429.
The non-strong version is A332296.
The case of partitions is A332297.
The co-strong version is A332336 (this sequence).
The wide version is A332337.

Programs

  • Mathematica
    tinQ[q_]:=Or[q=={},Length[q]==1,And[Union[q]==Range[Max[q]],GreaterEqual@@Length/@Split[q],tinQ[Length/@Split[q]]]];
    Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],tinQ]],{n,0,10}]

Formula

For n > 1, a(n) = A332337(n) + 1.

A332279 Number of widely totally normal compositions of n.

Original entry on oeis.org

1, 1, 1, 3, 4, 6, 12, 22, 29, 62, 119, 208, 368, 650, 1197, 2173, 3895, 7022, 12698, 22940, 41564
Offset: 0

Views

Author

Gus Wiseman, Feb 12 2020

Keywords

Comments

A sequence is widely totally normal if either it is all 1's (wide) or it covers an initial interval of positive integers (normal) and has widely totally normal run-lengths.
A composition of n is a finite sequence of positive integers with sum n.

Examples

			The a(1) = 1 through a(7) = 22 compositions:
  (1)  (11)  (12)   (112)   (122)    (123)     (1123)
             (21)   (121)   (212)    (132)     (1132)
             (111)  (211)   (221)    (213)     (1213)
                    (1111)  (1121)   (231)     (1231)
                            (1211)   (312)     (1312)
                            (11111)  (321)     (1321)
                                     (1212)    (2113)
                                     (1221)    (2122)
                                     (2112)    (2131)
                                     (2121)    (2212)
                                     (11211)   (2311)
                                     (111111)  (3112)
                                               (3121)
                                               (3211)
                                               (11221)
                                               (12112)
                                               (12121)
                                               (12211)
                                               (21121)
                                               (111211)
                                               (112111)
                                               (1111111)
For example, starting with y = (3,2,1,1,2,2,2,1,2,1,1,1,1) and repeatedly taking run-lengths gives y -> (1,1,2,3,1,1,4) -> (2,1,1,2,1) -> (1,2,1,1) -> (1,1,2) -> (2,1) -> (1,1). These are all normal and the last is all 1's, so y is counted under a(20).
		

Crossrefs

Normal compositions are A107429.
Constantly recursively normal partitions are A332272.
The case of partitions is A332277.
The case of reversed partitions is (also) A332277.
The narrow version is A332296.
The strong version is A332337.
The co-strong version is (also) A332337.

Programs

  • Mathematica
    recnQ[ptn_]:=Or[ptn=={},Union[ptn]=={1},And[Union[ptn]==Range[Max[ptn]],recnQ[Length/@Split[ptn]]]];
    Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],recnQ]],{n,0,10}]

Formula

For n > 1, a(n) = A332296(n) - 1.
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