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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A259794 Number of partitions of n^5 into fifth powers.

Original entry on oeis.org

1, 1, 2, 9, 88, 1104, 15772, 241582, 3869852, 63689650, 1065023018, 17948615155, 303219868652, 5116273886322, 86004191773864, 1437703756689091, 23869446608034827, 393225674878151704, 6423761195925513669, 104014146020398166139, 1668870762057827073994
Offset: 0

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Author

N. J. A. Sloane, Jul 06 2015

Keywords

Crossrefs

A row of the array in A259799.

Formula

a(n) = [x^(n^5)] Product_{k>=1} 1/(1 - x^(k^5)). - Ilya Gutkovskiy, Jan 29 2018

Extensions

More terms from Alois P. Heinz, Jul 10 2015

A259795 Number of partitions of n^6 into sixth powers.

Original entry on oeis.org

1, 1, 2, 13, 218, 5082, 140549, 4318937, 142230196, 4899174096, 173759831765, 6275666535508, 229029623773326, 8400986623582879, 308552577080828413, 11315799255444002331, 413526899811283611529, 15035521464541449037361, 543292158617220114038102, 19493012206795963934830852, 694033371089826655280448205, 24509565267500567956406898725
Offset: 0

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Author

N. J. A. Sloane, Jul 06 2015

Keywords

Crossrefs

A row of the array in A259799.

Formula

a(n) = [x^(n^6)] Product_{k>=1} 1/(1 - x^(k^6)). - Ilya Gutkovskiy, Jan 29 2018

Extensions

a(8)-a(14) from Alois P. Heinz, Jul 10 2015
a(15)-a(18) from Hiroaki Yamanouchi, Jul 11 2015
a(19)-a(21) from Vaclav Kotesovec, Dec 10 2016

A307608 Number of partitions of n^2 into consecutive positive squares.

Original entry on oeis.org

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

Views

Author

Ilya Gutkovskiy, Apr 18 2019

Keywords

Examples

			29^2 = 20^2 + 21^2, so a(29) = 2.
		

Crossrefs

Formula

a(n) = [x^(n^2)] Sum_{i>=1} Sum_{j>=i} Product_{k=i..j} x^(k^2).
a(n) = A296338(A000290(n)).
a(n) >= 2 for n in A097812.

A072925 Probably an erroneous version of A002845.

Original entry on oeis.org

1, 1, 1, 2, 4, 8, 17, 36, 78, 171, 379, 888, 1944
Offset: 1

Views

Author

Keywords

Comments

The old entry with this sequence number was a duplicate of A037444.

References

  • J. Q. Longyear, personal communication.
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences. San Diego, CA: Academic Press, 1995; entry M1139.

A229541 Number T(n,k) of partitions of n^2 into squares with each number of parts k; irregular triangle T(n,k), 1 <= k <= n^2.

Original entry on oeis.org

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

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Author

Keywords

Comments

Row sums give A037444.

Examples

			The irregular triangle begins:
\ k  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 ...
n
1    1
2    1  0  0  1
3    1  0  1  0  0  1  0  0  1
4    1  0  0  1  1  0  1  1  0  1  0  0  1  0  0  1
5    1  0  1  1  1  2  1  1  2  1  0  1  1  0  1  1  0  1 ...
6    1  0  1  2  1  4  1  1  4  2  1  4  2  1  2  1  1  2 ...
7    1  0  1  2  2  3  4  5  3  6  6  2  5  5  2  5  4  2 ...
8    1  0  0  1  5  2  7  9  5 11  8  5 12  8  6 12  8  6 ...
9    1  0  3  2  2 10  9  9 16 16 14 17 16 14 19 18 13 20 ...
Length of row n is n^2.
For n = 3, the 4 partitions are:
Square side 1 2 3    Number of Parts
            9 0 0           9
            5 1 0           6
            1 2 0           3
            0 0 1           1
As each partition has a different number of parts,
T(3,1) = 1, T(3,3) = 1, T(3,6) = 1, T(3,9) = 1.
		

Crossrefs

Cf. A037444.

Formula

It appears that T(n+1,g(n+1):(n+1)^2) = T(n,f(n):n^2) where f(1) = 1, f(2) = 1, f(n) = Sum(floor(n/2)), n >= 3, g(2) = 4, g(3) = 6, g(n) = Sum(floor((n+3)/2)) + 5, n >= 4. In addition, g(n+1) - f(n) = 2n + 1 for all n.

A229961 T(n,k) is the number of partitions in each run k of strictly increasing numbers of 2 X 2 squares in the list of partitions of n^2 into squares, where partition sorting order is ascending with larger squares taking higher precedence; irregular triangle T(n,k), 1 <= n, 1 <= k <= A227940(n), read by rows.

Original entry on oeis.org

1, 2, 3, 1, 5, 2, 1, 7, 5, 2, 3, 1, 1, 10, 7, 5, 3, 1, 6, 3, 1, 2, 3, 1, 1, 13, 11, 8, 6, 4, 2, 9, 7, 4, 2, 5, 3, 1, 7, 4, 2, 3, 4, 2, 1, 17, 14, 12, 10, 8, 5, 3, 1, 13, 10, 8, 6, 4, 1, 9, 6, 4, 2, 5, 2, 1, 10, 8, 6, 4, 1, 6, 4, 2, 2, 4, 2, 8, 5, 3, 1, 4, 1, 1, 4, 2, 1
Offset: 1

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Author

Keywords

Comments

Row lengths are given by A227940.

Examples

			For n = 4, the 8 partitions of 16 into square parts are:
Partition  Square side
.           1  2  3  4
.
.    1     16  0  0  0
.    2     12  1  0  0
.    3      8  2  0  0
.    4      4  3  0  0
.    5      0  4  0  0
.    6      7  0  1  0
.    7      3  1  1  0
.    8      0  0  0  1
So T(4,1) = 5 as the first runs of 2 X 2 squares is (0,1,2,3,4) from partitions 1 to 5;
T(4,2) = 2 as the second run is (0,1) from partitions 6 to 7;
T(4,3) = 1 as the third run is (0) from partition 8.
The irregular triangle begins:
  \  k  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 ...
  n
  1     1
  2     2
  3     3  1
  4     5  2  1
  5     7  5  2  3  1  1
  6    10  7  5  3  1  6  3  1  2  3  1  1
  7    13 11  8  6  4  2  9  7  4  2  5  3  1  7  4  2  3  4 ...
  8    17 14 12 10  8  5  3  1 13 10  8  6  4  1  9  6  4  2 ...
  9    21 19 16 14 12 10  7  5  3  1 17 15 12 10  8  6  3  1 ...
  10   26 23 21 19 17 14 12 10  8  5  3  1 22 19 17 15 13 10 ...
		

Crossrefs

Row sums = A037444.
Cf. A227940.

A321183 a(n) = [x^((n*(n+1)/2)^2)] Product_{k=1..n} Sum_{m>=0} x^(k^2*m).

Original entry on oeis.org

1, 1, 3, 26, 438, 11674, 434613, 21040885, 1263748763, 91057116368, 7676892453542, 742890018054927, 81267790173334794, 9926903213704358577, 1340280764681712515084, 198320073897808037293388, 31929177807445245255119558, 5558580993355817894674501169, 1040777481846356463369367882750
Offset: 0

Views

Author

Seiichi Manyama, Oct 29 2018

Keywords

Comments

Also the number of nonnegative integer solutions (a_1, a_2, ... , a_n) to the equation 1^2*a_1 + 2^2*a_2 + ... + n^2*a_n = (n*(n+1)/2)^2.

Examples

			1^2* 0 + 2^2*0 + 3^2*4 = 36.
1^2* 0 + 2^2*9 + 3^2*0 = 36.
1^2* 1 + 2^2*2 + 3^2*3 = 36.
1^2* 2 + 2^2*4 + 3^2*2 = 36.
1^2* 3 + 2^2*6 + 3^2*1 = 36.
1^2* 4 + 2^2*8 + 3^2*0 = 36.
1^2* 5 + 2^2*1 + 3^2*3 = 36.
1^2* 6 + 2^2*3 + 3^2*2 = 36.
1^2* 7 + 2^2*5 + 3^2*1 = 36.
1^2* 8 + 2^2*7 + 3^2*0 = 36.
1^2* 9 + 2^2*0 + 3^2*3 = 36.
1^2*10 + 2^2*2 + 3^2*2 = 36.
1^2*11 + 2^2*4 + 3^2*1 = 36.
1^2*12 + 2^2*6 + 3^2*0 = 36.
1^2*14 + 2^2*1 + 3^2*2 = 36.
1^2*15 + 2^2*3 + 3^2*1 = 36.
1^2*16 + 2^2*5 + 3^2*0 = 36.
1^2*18 + 2^2*0 + 3^2*2 = 36.
1^2*19 + 2^2*2 + 3^2*1 = 36.
1^2*20 + 2^2*4 + 3^2*0 = 36.
1^2*23 + 2^2*1 + 3^2*1 = 36.
1^2*24 + 2^2*3 + 3^2*0 = 36.
1^2*27 + 2^2*0 + 3^2*1 = 36.
1^2*28 + 2^2*2 + 3^2*0 = 36.
1^2*32 + 2^2*1 + 3^2*0 = 36.
1^2*36 + 2^2*0 + 3^2*0 = 36.
So a(3) = 26.
		

Crossrefs

Extensions

a(16)-a(18) from Alois P. Heinz, Oct 29 2018

A092179 Number of partitions of n^2 into squares providing no dissections of the square n X n into smaller squares.

Original entry on oeis.org

0, 0, 1, 1, 8, 12, 41, 72, 192, 362, 909, 1524, 3699, 6928, 14235, 25296
Offset: 1

Views

Author

Reinhard Zumkeller, Apr 02 2004

Keywords

Comments

a(n) = A037444(n) - A034295(n).

Extensions

a(9)-a(12) from Alois P. Heinz, Apr 15 2013
a(13) from Alois P. Heinz, May 30 2013
a(14) from Christopher Hunt Gribble, Oct 26 2013
Values a(15)-a(16) computed using A034295 from Vaclav Kotesovec, Dec 07 2016

A276557 Number of partitions of prime(n)^2 into squares of primes.

Original entry on oeis.org

1, 1, 2, 4, 17, 39, 191, 410, 1771, 13805, 26459, 170897, 556698, 988053, 3019206, 15074481, 70202708, 115639004, 498047289, 1281427052, 2039282754, 7981334946, 19374343049, 71015123687, 380553620426, 862797574415, 1292837481584, 2875949125749, 4270259833946, 9334145396729
Offset: 1

Views

Author

Ilya Gutkovskiy, Jun 14 2017

Keywords

Examples

			a(3) = 2 because third square of prime is 25 and we have [25], [9, 4, 4, 4, 4].
		

Crossrefs

Programs

  • Mathematica
    Table[SeriesCoefficient[Product[1/(1 - x^Prime[k]^2), {k, 1, n}], {x, 0, Prime[n]^2}], {n, 1, 30}]

Formula

a(n) = [x^(prime(n)^2)] Product_{k>=1} 1/(1 - x^(prime(k)^2)).
a(n) = A090677(A001248(n)).

A294071 Number of ordered ways of writing n^2 as a sum of n squares > 1.

Original entry on oeis.org

1, 0, 0, 0, 1, 5, 6, 7, 288, 262, 13702, 69531, 610567, 5356091, 51724960, 521956086, 5467658641, 59931636545, 690518644584, 8100858045744, 99142980567486, 1246972499954475, 16142015005905558, 215722810653380845, 2955759897694815985, 41614888439136252691
Offset: 0

Views

Author

Ilya Gutkovskiy, Feb 07 2018

Keywords

Examples

			a(5) = 5 because we have [9, 4, 4, 4, 4], [4, 9, 4, 4, 4], [4, 4, 9, 4, 4], [4, 4, 4, 9, 4] and [4, 4, 4, 4, 9].
		

Crossrefs

Programs

  • Mathematica
    Table[SeriesCoefficient[((-1 - 2 x + EllipticTheta[3, 0, x])/2)^n, {x, 0, n^2}], {n, 0, 25}]

Formula

a(n) = [x^(n^2)] (Sum_{k>=2} x^(k^2))^n.
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