A073118
Total sum of prime parts in all partitions of n.
Original entry on oeis.org
0, 2, 5, 9, 19, 33, 57, 87, 136, 206, 311, 446, 650, 914, 1284, 1762, 2432, 3276, 4433, 5888, 7824, 10272, 13479, 17471, 22642, 29087, 37283, 47453, 60306, 76112, 95931, 120201, 150338, 187141, 232507, 287591, 355143, 436849, 536347, 656282, 801647, 976095
Offset: 1
From _Omar E. Pol_, Nov 20 2011 (Start):
For n = 6 we have:
--------------------------------------
. Sum of
Partitions prime parts
--------------------------------------
6 .......................... 0
3 + 3 ...................... 6
4 + 2 ...................... 2
2 + 2 + 2 .................. 6
5 + 1 ...................... 5
3 + 2 + 1 .................. 5
4 + 1 + 1 .................. 0
2 + 2 + 1 + 1 .............. 4
3 + 1 + 1 + 1 .............. 3
2 + 1 + 1 + 1 + 1 .......... 2
1 + 1 + 1 + 1 + 1 + 1 ...... 0
--------------------------------------
Total ..................... 33
So a(6) = 33. (End)
-
b:= proc(n, i) option remember; local h, j, t;
if n<0 then [0, 0]
elif n=0 then [1, 0]
elif i<1 then [0, 0]
else h:= [0, 0];
for j from 0 to iquo(n, i) do
t:= b(n-i*j, i-1);
h:= [h[1]+t[1], h[2]+t[2]+`if`(isprime(i), t[1]*i*j, 0)]
od; h
fi
end:
a:= n-> b(n, n)[2]:
seq(a(n), n=1..50); # Alois P. Heinz, Nov 20 2011
-
f[n_] := Apply[Plus, Select[ Flatten[ IntegerPartitions[n]], PrimeQ[ # ] & ]]; Table[ f[n], {n, 1, 41} ]
a[n_] := Sum[Total[FactorInteger[k][[All, 1]]]*PartitionsP[n-k], {k, 1, n}] - PartitionsP[n-1]; Array[a, 50] (* Jean-François Alcover, Dec 27 2015 *)
-
a(n)={sum(k=1, n, vecsum(factor(k)[, 1])*numbpart(n-k))} \\ Andrew Howroyd, Dec 28 2017
A102291
Total number of prime parts in all compositions of n.
Original entry on oeis.org
0, 0, 1, 3, 7, 18, 42, 98, 222, 497, 1100, 2413, 5250, 11350, 24398, 52193, 111180, 235949, 499074, 1052502, 2213710, 4644833, 9724492, 20318637, 42376578, 88231765, 183420748, 380755932, 789340736, 1634339217, 3379993922, 6982618822, 14410499598, 29711523105
Offset: 0
-
a:= proc(n) option remember; `if`(n=0, 0, add(a(n-j)+
`if`(isprime(j), ceil(2^(n-j-1)), 0), j=1..n))
end:
seq(a(n), n=0..33); # Alois P. Heinz, Aug 06 2019
-
a[n_] := a[n] = If[n==0, 0, Sum[a[n-j] + If[PrimeQ[j], Ceiling[2^(n-j-1)], 0], {j, 1, n}]];
a /@ Range[0, 33] (* Jean-François Alcover, Oct 30 2020, after Alois P. Heinz *)
A144115
Total number of Fibonacci parts in all partitions of n.
Original entry on oeis.org
1, 3, 6, 11, 19, 32, 49, 77, 114, 169, 241, 345, 480, 667, 910, 1237, 1656, 2213, 2918, 3840, 5003, 6497, 8368, 10751, 13711, 17441, 22052, 27806, 34879, 43645, 54355, 67535, 83571, 103171, 126907, 155766, 190554, 232629, 283158, 343969, 416716, 503900, 607807
Offset: 1
From _Omar E. Pol_, Nov 20 2011 (Start):
For n = 6 we have:
--------------------------------------
. Number of
Partitions Fibonacci parts
--------------------------------------
6 .......................... 0
3 + 3 ...................... 2
4 + 2 ...................... 1
2 + 2 + 2 .................. 3
5 + 1 ...................... 2
3 + 2 + 1 .................. 3
4 + 1 + 1 .................. 2
2 + 2 + 1 + 1 .............. 4
3 + 1 + 1 + 1 .............. 4
2 + 1 + 1 + 1 + 1 .......... 5
1 + 1 + 1 + 1 + 1 + 1 ...... 6
------------------------------------
Total ..................... 32
So a(6) = 32. (End)
-
b:= proc(n, i) option remember; `if`(n=0, [1, 0], `if`(i<1, 0,
b(n, i-1)+ (p-> p+`if`((t-> issqr(t+4) or issqr(t-4)
)(5*i^2), [0, p[1]], 0))(b(n-i, min(n-i, i)))))
end:
a:= n-> b(n$2)[2]:
seq(a(n), n=1..60); # Alois P. Heinz, Jun 24 2009, revised Aug 06 2019
-
Clear[b]; b[] = False; l = {0, 1}; For[k=1, k <= 100, k++, b[l[[1]]] = True; l = {l[[2]], l[[1]] + l[[2]]}]; aa[n, i_] := aa[n, i] = Module[{g, h}, If[n==0, {1, 0}, If[i==0 || n<0, {0, 0}, g = aa[n, i-1]; h = aa[n-i, i]; {g[[1]] + h[[1]], g[[2]] + h[[2]] + If[b[i], h[[1]], 0]}]]]; a[n_] := aa[n, n][[2]]; Table[a[n], {n, 1, 60}] (* Jean-François Alcover, Jul 30 2015, after Alois P. Heinz *)
A222656
Number T(n,k) of partitions of n using exactly k primes; triangle T(n,k), n>=0, 0<=k<=floor(n/2), read by rows.
Original entry on oeis.org
1, 1, 1, 1, 1, 2, 2, 2, 1, 2, 3, 2, 3, 4, 3, 1, 3, 6, 4, 2, 5, 7, 6, 3, 1, 6, 9, 8, 5, 2, 8, 11, 12, 7, 3, 1, 8, 17, 14, 10, 5, 2, 12, 20, 19, 14, 8, 3, 1, 13, 26, 25, 19, 11, 5, 2, 17, 31, 35, 24, 16, 8, 3, 1, 19, 41, 42, 34, 21, 12, 5, 2, 26, 47, 56, 44, 29
Offset: 0
T(6,0) = 3: [6], [4,1,1], [1,1,1,1,1,1].
T(6,1) = 4: [5,1], [4,2], [3,1,1,1], [2,1,1,1,1].
T(6,2) = 3: [3,3], [3,2,1], [2,2,1,1].
T(6,3) = 1: [2,2,2].
Triangle T(n,k) begins:
1;
1;
1, 1;
1, 2;
2, 2, 1;
2, 3, 2;
3, 4, 3, 1;
3, 6, 4, 2;
5, 7, 6, 3, 1;
6, 9, 8, 5, 2;
8, 11, 12, 7, 3, 1;
8, 17, 14, 10, 5, 2;
...
-
b:= proc(n, i) option remember; local j; if n=0 then 1 elif i<1 then 0
else []; for j from 0 to n/i do zip((x, y)->x+y, %,
[`if`(isprime(i), 0$j, NULL), b(n-i*j, i-1)], 0) od; %[] fi
end:
T:= n-> b(n$2):
seq(T(n), n=0..16);
-
zip[f_, x_List, y_List, z_] := With[{m = Max[Length[x], Length[y]]}, Thread[f[PadRight[x, m, z], PadRight[y, m, z]]]]; b[n_, i_] := b[n, i] = Module[{j, pc}, Which[n == 0, {1}, i<1, {0}, True, pc = {}; For[j = 0, j <= n/i, j++, pc = zip[Plus, pc, Join[If[PrimeQ[i], Array[0&, j], {}], b[n-i*j, i-1]], 0]]; pc]]; T[n_] := b[n, n]; Table[T[n], {n, 0, 16}] // Flatten (* Jean-François Alcover, Jan 29 2014, after Alois P. Heinz *)
A073335
Total number of prime power parts in all partitions of n.
Original entry on oeis.org
0, 1, 2, 5, 8, 15, 23, 39, 58, 89, 128, 189, 264, 375, 515, 713, 960, 1301, 1726, 2298, 3011, 3948, 5113, 6625, 8492, 10880, 13825, 17545, 22108, 27823, 34800, 43465, 54003, 66983, 82709, 101960, 125180, 153432, 187397, 228490, 277707, 336972
Offset: 1
a(4)=5 because in all partitions of 4 we have 5 powers of primes (shown between parentheses): (4), (3)1, (2)(2), (2)11, 1111.
-
with(numtheory): with(combinat): a:= n-> add(bigomega(k)*numbpart(n-k), k=1..n): seq(a(n), n=1..46); # Emeric Deutsch, Feb 26 2005
-
Table[Sum[PrimeOmega[k]*PartitionsP[n - k], {k, 1, n}], {n, 1, 50}] (* G. C. Greubel, May 05 2017 *)
-
a(n) = sum(k=1, n, bigomega(k)*numbpart(n-k)); \\ Michel Marcus, May 05 2017
A144119
Total number of nonprime parts in all partitions of n.
Original entry on oeis.org
1, 2, 4, 8, 13, 22, 34, 54, 80, 119, 170, 246, 342, 478, 653, 894, 1198, 1610, 2127, 2813, 3672, 4789, 6181, 7975, 10192, 13010, 16488, 20861, 26224, 32918, 41086, 51199, 63494, 78599, 96888, 119235, 146167, 178879, 218181, 265662, 322487, 390834, 472343
Offset: 1
From _Omar E. Pol_, Nov 20 2011 (Start):
For n = 6 we have:
--------------------------------------
. Number of
Partitions nonprime parts
--------------------------------------
6 .......................... 1
3 + 3 ...................... 0
4 + 2 ...................... 1
2 + 2 + 2 .................. 0
5 + 1 ...................... 1
3 + 2 + 1 .................. 1
4 + 1 + 1 .................. 3
2 + 2 + 1 + 1 .............. 2
3 + 1 + 1 + 1 .............. 3
2 + 1 + 1 + 1 + 1 .......... 4
1 + 1 + 1 + 1 + 1 + 1 ...... 6
------------------------------------
Total ..................... 22
So a(6) = 22. (End)
-
b:= proc(n, i) option remember; local g;
if n=0 then [1, 0]
elif i<1 then [0, 0]
else g:= `if`(i>n, [0$2], b(n-i, i));
b(n, i-1) +g +[0, `if`(isprime(i), 0, g[1])]
fi
end:
a:= n-> b(n, n)[2]:
seq(a(n), n=1..100); # Alois P. Heinz, Oct 27 2012
-
b[n_, i_] := b[n, i] = Module[{g}, If[n == 0, {1, 0}, If[i<1, {0, 0}, g = If[i>n, {0, 0}, b[n-i, i]]; b[n, i-1] + g + {0, If[PrimeQ[i], 0, g[[1]]]} ]]]; a[n_] := b[n, n][[2]]; Table[a[n], {n, 1, 100}] (* Jean-François Alcover, Oct 29 2015, after Alois P. Heinz *)
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vector(100, n, sum(k=1, n, (numdiv(k)-omega(k))*numbpart(n-k))) \\ Altug Alkan, Oct 29 2015
A144120
Number of prime parts in the last section of the set of partitions of n.
Original entry on oeis.org
0, 1, 1, 2, 3, 6, 7, 12, 16, 25, 32, 48, 61, 88, 113, 154, 198, 267, 337, 446, 563, 730, 915, 1174, 1460, 1853, 2294, 2878, 3545, 4416, 5404, 6679, 8144, 9991, 12125, 14791, 17866, 21677, 26084, 31478, 37733, 45340
Offset: 1
A183088
Total number of parts that are partition numbers A000041 in all partitions of n.
Original entry on oeis.org
0, 1, 3, 6, 11, 19, 32, 50, 77, 115, 170, 244, 348, 485, 674, 922, 1251, 1678, 2241, 2959, 3892, 5076, 6592, 8497, 10915, 13930, 17719, 22417, 28267, 35474, 44395, 55312, 68730, 85082, 105049, 129261, 158675, 194171, 237077, 288651
Offset: 0
a(5) = 19 because the 7 partitions of 5 are [5], [4, 1], [3, 2], [3, 1, 1], [2, 2, 1], [2, 1, 1, 1], [1, 1, 1, 1, 1] and we can see that there are 19 parts that are partition numbers A000041. Note that there are 20 parts but the 4 is not a partition number, so a(5) = 20 - 1 = 19.
-
A000041 = Table[PartitionsP[n], {n, 0, 45}]; Table[Length[Select[Flatten[IntegerPartitions[n]], MemberQ[A000041, #] &]], {n, 40}] (* Alonso del Arte, Aug 05 2011 *)
A281573
Expansion of Sum_{i>=1} mu(i)^2*x^i/(1 - x^i) / Product_{j>=1} (1 - x^j), where mu() is the Moebius function (A008683).
Original entry on oeis.org
1, 3, 6, 11, 19, 33, 51, 79, 118, 176, 252, 362, 505, 705, 965, 1314, 1765, 2365, 3127, 4124, 5387, 7012, 9052, 11653, 14893, 18982, 24048, 30378, 38176, 47857, 59704, 74302, 92099, 113879, 140300, 172463, 211297, 258325, 314887, 383037, 464684, 562653, 679566, 819269, 985449, 1183242, 1417738, 1695886
Offset: 1
a(5) = 19 because we have [5], [4, 1], [3, 2], [3, 1, 1], [2, 2, 1], [2, 1, 1, 1], [1, 1, 1, 1, 1] and 1 + 1 + 2 + 3 + 3 + 4 + 5 = 19.
-
nmax = 48; Rest[CoefficientList[Series[Sum[MoebiusMu[i]^2 x^i/(1 - x^i), {i, 1, nmax}]/Product[1 - x^j, {j, 1, nmax}], {x, 0, nmax}], x]]
A326957
Total number of noncomposite parts in all partitions of n.
Original entry on oeis.org
0, 1, 3, 6, 11, 19, 32, 50, 77, 115, 170, 244, 348, 486, 675, 923, 1253, 1682, 2246, 2968, 3904, 5094, 6616, 8533, 10962, 13997, 17808, 22538, 28426, 35689, 44670, 55678, 69199, 85692, 105826, 130261, 159935, 195778, 239092, 291191, 353854, 428925, 518848
Offset: 0
For n = 6 we have:
--------------------------------------
. Number of
Partitions noncomposite
of 6 parts
--------------------------------------
6 .......................... 0
3 + 3 ...................... 2
4 + 2 ...................... 1
2 + 2 + 2 .................. 3
5 + 1 ...................... 2
3 + 2 + 1 .................. 3
4 + 1 + 1 .................. 2
2 + 2 + 1 + 1 .............. 4
3 + 1 + 1 + 1 .............. 4
2 + 1 + 1 + 1 + 1 .......... 5
1 + 1 + 1 + 1 + 1 + 1 ...... 6
------------------------------------
Total ..................... 32
So a(6) = 32.
First differs from
A183088 at a(13).
-
b:= proc(n, i) option remember; `if`(n=0 or i=1, [1, n], b(n, i-1)+
(p-> p+[0, `if`(isprime(i), p[1], 0)])(b(n-i, min(n-i, i))))
end:
a:= n-> b(n$2)[2]:
seq(a(n), n=0..50); # Alois P. Heinz, Aug 13 2019
-
b[n_] := Sum[PrimeNu[k] PartitionsP[n-k], {k, 1, n}];
c[n_] := SeriesCoefficient[Product[1/(1-x^k), {k, 1, n}]/(1-x), {x, 0, n}];
a[n_] := b[n] + c[n-1];
a /@ Range[0, 50] (* Jean-François Alcover, Nov 15 2020 *)
Showing 1-10 of 14 results.
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