A290247
Number of compositions (ordered partitions) of n^3 into cubes.
Original entry on oeis.org
1, 1, 2, 120, 290250, 107320441096, 21715974961480054078, 8487986089807555456140271121440, 22615863021403796876556069287242400147213424924, 1449638083412288206280215383952017948209203861522683138464747658192
Offset: 0
a(2) = 2 because 2^3 = 8 and we have [8], [1, 1, 1, 1, 1, 1, 1, 1].
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b:= proc(n) option remember; local i; if n=0 then 1
else 0; for i while i^3<=n do %+b(n-i^3) od fi
end:
a:= n-> b(n^3):
seq(a(n), n=0..10); # Alois P. Heinz, Aug 12 2017
-
Table[SeriesCoefficient[1/(1 - Sum[x^k^3, {k, 1, n}]), {x, 0, n^3}], {n, 0, 9}]
A224677
Number of compositions of n*(n+1)/2 into sums of positive triangular numbers.
Original entry on oeis.org
1, 1, 2, 7, 40, 351, 4876, 104748, 3487153, 179921982, 14387581923, 1783124902639, 342504341570010, 101962565961894431, 47044167891731682278, 33640402686770010577421, 37282664267078280296013183, 64038780633654058635677191329, 170478465430659361252118580217675
Offset: 0
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b:= proc(n) option remember; local i; if n=0 then 1 else 0;
for i while i*(i+1)/2<=n do %+b(n-i*(i+1)/2) od; % fi
end:
a:= n-> b(n*(n+1)/2):
seq(a(n), n=0..20); # Alois P. Heinz, Feb 05 2018
-
b[n_] := b[n] = If[n==0, 1, Sum[If[IntegerQ[Sqrt[8j+1]], b[n-j], 0], {j, 1, n}]];
a[n_] := b[n(n+1)/2];
a /@ Range[0, 20] (* Jean-François Alcover, Oct 31 2020, after Alois P. Heinz in A023361 *)
-
{a(n)=polcoeff(1/(1-sum(r=1,n+1, x^(r*(r+1)/2)+x*O(x^(n*(n+1)/2)))), n*(n+1)/2)}
for(n=0, 20, print1(a(n), ", "))
A337764
Number of compositions (ordered partitions) of the n-th n-gonal number into n-gonal numbers.
Original entry on oeis.org
1, 1, 2, 7, 124, 14371, 12842911, 103590035354, 8621925847489749, 8307493939404888703058, 102488432265617100812550713499, 17706351554929677399562928448484650120, 46435685450659378932235460132506329282776942795
Offset: 0
a(3) = 7 because the third triangular number is 6 and we have [6], [3, 3], [3, 1, 1, 1], [1, 3, 1, 1], [1, 1, 3, 1], [1, 1, 1, 3] and [1, 1, 1, 1, 1, 1].
A224679
Number of compositions of n^2 into sums of positive triangular numbers.
Original entry on oeis.org
1, 1, 3, 25, 546, 28136, 3487153, 1038115443, 742336894991, 1275079195875471, 5260826667789867957, 52137661179700350278531, 1241165848412448464485760897, 70972288312605764017275784402928, 9748291749334923037419108242002717050
Offset: 0
-
b:= proc(n) option remember; local i; if n=0 then 1 else 0;
for i while i*(i+1)/2<=n do %+b(n-i*(i+1)/2) od; % fi
end:
a:= n-> b(n^2):
seq(a(n), n=0..20); # Alois P. Heinz, Feb 05 2018
-
b[n_] := b[n] = Module[{i, j = If[n == 0, 1, 0]}, For[i = 1, i(i+1)/2 <= n, i++, j += b[n-i(i+1)/2]]; j];
a[n_] := b[n^2];
a /@ Range[0, 20] (* Jean-François Alcover, Nov 04 2020, after Alois P. Heinz *)
-
{a(n)=polcoeff(1/(1-sum(r=1,n+1, x^(r*(r+1)/2)+x*O(x^(n^2)))), n^2)}
for(n=0, 20, print1(a(n), ", "))
A298640
Number of compositions (ordered partitions) of n^2 into squares > 1.
Original entry on oeis.org
1, 0, 1, 1, 2, 8, 12, 129, 874, 9630, 167001, 3043147, 72844510, 2423789655, 106665874384, 6156805673648, 470151743582651, 47558937432498729, 6363358599941131580, 1126147544855148769425, 263646401550138303553708, 81649922556593759124887197
Offset: 0
a(5) = 8 because we have [25], [16, 9], [9, 16], [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].
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b:= proc(n) option remember; `if`(n=0, 1,
add(b(n-j^2), j=2..isqrt(n)))
end:
a:= n-> b(n^2):
seq(a(n), n=0..25); # Alois P. Heinz, Feb 05 2018
-
b[n_] := b[n] = If[n == 0, 1, Sum[b[n - j^2], {j, 2, Floor @ Sqrt[n]}]];
a[n_] := b[n^2];
Table[a[n], {n, 0, 25}] (* Jean-François Alcover, May 21 2018, after Alois P. Heinz *)
Original entry on oeis.org
1, 5, 28, 269, 6181, 286790, 26808447, 5037694829, 1902773895751, 1444565587750055, 2204357811343981558, 6761166975496300074014, 41682712965722542326438411, 516517498759950258411494666787, 12864972023450485679400300069493738
Offset: 1
L.g.f.: L(x) = x + 5*x^2/2 + 28*x^3/3 + 269*x^4/4 + 6181*x^5/5 + 286790*x^6/6 +...
where
exp(L(x)) = 1 + x + 3*x^2 + 12*x^3 + 81*x^4 + 1335*x^5 + 49309*x^6 + 3882180*x^7 +...+ A224608(n)*x^n +...
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{a(n)=n^2*polcoeff(-log(1-sum(r=1,n,x^(r^2)+x*O(x^(n^2)))),n^2)}
for(n=1,30,print1(a(n),", "))
A224608
G.f.: exp( Sum_{n>=1} A219331(n^2)*x^n/n ).
Original entry on oeis.org
1, 1, 3, 12, 81, 1335, 49309, 3882180, 633703214, 212061201327, 144669917959584, 200541263416077021, 563631413420071614333, 3206926569346230863485855, 36897315109526505791310840932, 857701705296285206387609947414980, 40254707002970300021370965171570478599
Offset: 0
G.f.: A(x) = 1 + x + 3*x^2 + 12*x^3 + 81*x^4 + 1335*x^5 + 49309*x^6 +...
where
log(A(x)) = x + 5*x^2/2 + 28*x^3/3 + 269*x^4/4 + 6181*x^5/5 + 286790*x^6/6 +...+ A219331(n^2)*x^n/n +...
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{A219331(n)=n*polcoeff(-log(1-sum(r=1,sqrtint(n+1),x^(r^2)+x*O(x^n))),n)}
{a(n)=polcoeff(exp(sum(m=1,n,A219331(m^2)*x^m/m)+x*O(x^n)),n)}
for(n=0,20,print1(a(n),", "))
A331884
Number of compositions (ordered partitions) of n^2 into distinct squares.
Original entry on oeis.org
1, 1, 1, 1, 1, 3, 1, 7, 1, 31, 123, 151, 121, 897, 7351, 5415, 14881, 48705, 150583, 468973, 1013163, 1432471, 1730023, 50432107, 14925241, 125269841, 74592537, 241763479, 213156871, 895153173, 7716880623, 2681163865, 3190865761, 22501985413, 116279718801
Offset: 0
a(5) = 3 because we have [25], [16, 9] and [9, 16].
Cf.
A000290,
A006456,
A030273,
A032020,
A037444,
A105152,
A224366,
A232173,
A280129,
A298640,
A331844.
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b:= proc(n, i, p) option remember;
`if`(i*(i+1)*(2*i+1)/6n, 0, b(n-i^2, i-1, p+1))+b(n, i-1, p)))
end:
a:= n-> b(n^2, n, 0):
seq(a(n), n=0..35); # Alois P. Heinz, Jan 30 2020
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b[n_, i_, p_] := b[n, i, p] = If[i(i+1)(2i+1)/6 < n, 0, If[n == 0, p!, If[i^2 > n, 0, b[n - i^2, i - 1, p + 1]] + b[n, i - 1, p]]];
a[n_] := b[n^2, n, 0];
a /@ Range[0, 35] (* Jean-François Alcover, Nov 08 2020, after Alois P. Heinz *)
A347590
Number of compositions (ordered partitions) of n^2 into at most n squares.
Original entry on oeis.org
1, 1, 1, 4, 2, 20, 188, 1031, 8777, 62528, 437160, 4185739, 38642386, 383969125, 4149154916, 45160025119, 514181220266, 6133093344169, 75135177511922, 962729735639323, 12745694628358530, 173304634479902187, 2433186864257121180, 35030916937968941062
Offset: 0
A232266
Triangle where T(n,k) = number of compositions of n^2 - k^2 into sums of squares for k=0..n, n>=0, as read by rows.
Original entry on oeis.org
1, 1, 1, 2, 1, 1, 11, 7, 3, 1, 124, 88, 30, 5, 1, 2870, 2024, 710, 124, 11, 1, 133462, 94137, 33033, 5767, 502, 22, 1, 12477207, 8800750, 3088365, 539192, 46832, 2024, 43, 1, 2344649612, 1653790807, 580347968, 101321507, 8800750, 380315, 8176, 88, 1, 885591183971, 624648802700, 219201637352, 38269865019, 3324109524, 143647802, 3088365, 33033, 175, 1
Offset: 0
Triangle begins:
1;
1, 1;
2, 1, 1;
11, 7, 3, 1;
124, 88, 30, 5, 1;
2870, 2024, 710, 124, 11, 1;
133462, 94137, 33033, 5767, 502, 22, 1;
12477207, 8800750, 3088365, 539192, 46832, 2024, 43, 1;
2344649612, 1653790807, 580347968, 101321507, 8800750, 380315, 8176, 88, 1;
885591183971, 624648802700, 219201637352, 38269865019, 3324109524, 143647802, 3088365, 33033, 175, 1; ...
where T(n,k) = coefficient of x^(n^2-k^2) in the series:
1/(1 - x - x^4 - x^9 - x^16 - x^25 - x^36 -...- x^(n^2) -...) = 1 + x + x^2 + x^3 + 2*x^4 + 3*x^5 + 4*x^6 + 5*x^7 + 7*x^8 + 11*x^9 + 16*x^10 + 22*x^11 + 30*x^12 + 43*x^13 + 62*x^14 + 88*x^15 + 124*x^16 + 175*x^17 + 249*x^18 + 354*x^19 + 502*x^20 + 710*x^21 + 1006*x^22 + 1427*x^23 + 2024*x^24 + 2870*x^25 +...
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{T(n,k)=polcoeff(1/(1-sum(m=1,n+1,x^(m^2))+x*O(x^(n^2-k^2))),n^2-k^2)}
for(n=0,10,for(k=0,n,print1(T(n,k),", "));print(""))
Showing 1-10 of 12 results.
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