A340960
Number of ways to write n as an ordered sum of 4 primes.
Original entry on oeis.org
1, 4, 6, 8, 13, 16, 22, 24, 22, 32, 34, 40, 47, 48, 56, 68, 70, 76, 90, 84, 111, 112, 126, 120, 144, 120, 176, 140, 184, 148, 226, 168, 264, 184, 262, 196, 313, 192, 352, 208, 366, 256, 418, 240, 473, 260, 496, 324, 536, 300, 616, 308, 634, 348, 670, 348, 772, 364, 786, 412
Offset: 8
Cf.
A000040,
A010051,
A073610,
A098238,
A259194,
A340961,
A340962,
A340963,
A340964,
A340965,
A340966.
-
b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 4):
seq(a(n), n=8..67); # Alois P. Heinz, Jan 31 2021
-
nmax = 67; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^4, {x, 0, nmax}], x] // Drop[#, 8] &
A340961
Number of ways to write n as an ordered sum of 5 primes.
Original entry on oeis.org
1, 5, 10, 15, 25, 36, 50, 65, 70, 90, 110, 125, 155, 170, 200, 241, 270, 300, 350, 375, 435, 500, 530, 600, 640, 696, 760, 850, 840, 985, 990, 1170, 1160, 1370, 1250, 1570, 1445, 1760, 1600, 2000, 1710, 2340, 1950, 2555, 2165, 2876, 2320, 3340, 2560, 3595, 2880, 3985, 3050
Offset: 10
Cf.
A000040,
A010051,
A073610,
A098238,
A259195,
A340960,
A340962,
A340963,
A340964,
A340965,
A340966.
-
b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 5):
seq(a(n), n=10..62); # Alois P. Heinz, Jan 31 2021
-
nmax = 62; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^5, {x, 0, nmax}], x] // Drop[#, 10] &
A340962
Number of ways to write n as an ordered sum of 6 primes.
Original entry on oeis.org
1, 6, 15, 26, 45, 72, 106, 150, 186, 236, 306, 366, 455, 540, 636, 782, 912, 1056, 1236, 1410, 1617, 1896, 2106, 2400, 2696, 2976, 3348, 3716, 4026, 4446, 4917, 5340, 5982, 6380, 7017, 7476, 8377, 8640, 9765, 9936, 11202, 11496, 13132, 12930, 15117, 14672, 17178, 16800, 19696
Offset: 12
Cf.
A000040,
A010051,
A073610,
A098238,
A259196,
A340960,
A340961,
A340963,
A340964,
A340965,
A340966.
-
b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 6):
seq(a(n), n=12..60); # Alois P. Heinz, Jan 31 2021
-
nmax = 60; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^6, {x, 0, nmax}], x] // Drop[#, 12] &
A340963
Number of ways to write n as an ordered sum of 7 primes.
Original entry on oeis.org
1, 7, 21, 42, 77, 133, 210, 316, 434, 574, 770, 980, 1239, 1547, 1876, 2331, 2828, 3367, 4032, 4746, 5565, 6574, 7602, 8757, 10136, 11480, 13132, 14882, 16646, 18662, 20951, 23268, 26082, 28861, 31787, 35218, 38745, 42532, 46403, 50883, 54810, 60613, 65016, 71302, 76069
Offset: 14
Cf.
A000040,
A010051,
A073610,
A098238,
A259197,
A340960,
A340961,
A340962,
A340964,
A340965,
A340966.
-
b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 7):
seq(a(n), n=14..58); # Alois P. Heinz, Jan 31 2021
-
nmax = 58; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^7, {x, 0, nmax}], x] // Drop[#, 14] &
A340964
Number of ways to write n as an ordered sum of 8 primes.
Original entry on oeis.org
1, 8, 28, 64, 126, 232, 392, 624, 925, 1296, 1800, 2416, 3158, 4088, 5152, 6504, 8142, 9976, 12216, 14784, 17738, 21296, 25272, 29736, 35023, 40768, 47328, 54832, 62728, 71744, 81796, 92736, 105078, 118664, 132924, 149424, 167002, 186144, 206852, 229272, 253023
Offset: 16
Cf.
A000040,
A010051,
A073610,
A098238,
A259198,
A340960,
A340961,
A340962,
A340963,
A340965,
A340966.
-
b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 8):
seq(a(n), n=16..56); # Alois P. Heinz, Jan 31 2021
-
nmax = 56; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^8, {x, 0, nmax}], x] // Drop[#, 16] &
A340965
Number of ways to write n as an ordered sum of 9 primes.
Original entry on oeis.org
1, 9, 36, 93, 198, 387, 696, 1170, 1845, 2740, 3960, 5562, 7566, 10125, 13248, 17133, 22014, 27774, 34776, 43173, 53010, 64869, 78696, 94617, 113415, 134946, 159552, 188164, 219960, 256041, 297180, 342846, 394614, 452595, 516276, 587997, 667938, 755109, 852444
Offset: 18
Cf.
A000040,
A010051,
A073610,
A098238,
A259200,
A340960,
A340961,
A340962,
A340963,
A340964,
A340966.
-
b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 9):
seq(a(n), n=18..56); # Alois P. Heinz, Jan 31 2021
-
nmax = 56; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^9, {x, 0, nmax}], x] // Drop[#, 18] &
A340966
Number of ways to write n as an ordered sum of 10 primes.
Original entry on oeis.org
1, 10, 45, 130, 300, 622, 1185, 2100, 3495, 5480, 8266, 12100, 17140, 23730, 32155, 42802, 56400, 73180, 93820, 119250, 149872, 187090, 231765, 284490, 347335, 421332, 507580, 608840, 725500, 859450, 1014473, 1190700, 1392100, 1621710, 1879950, 2172610, 2503580
Offset: 20
Cf.
A000040,
A010051,
A073610,
A098238,
A259201,
A340960,
A340961,
A340962,
A340963,
A340964,
A340965.
-
b:= proc(n, k) option remember; local r, p; r, p:= 0, 2;
if n=0 then `if`(k=0, 1, 0) elif k<1 then 0 else
while p<=n do r:= r+b(n-p, k-1); p:= nextprime(p) od; r fi
end:
a:= n-> b(n, 10):
seq(a(n), n=20..56); # Alois P. Heinz, Jan 31 2021
-
nmax = 56; CoefficientList[Series[Sum[x^Prime[k], {k, 1, nmax}]^10, {x, 0, nmax}], x] // Drop[#, 20] &
A224344
Number T(n,k) of compositions of n using exactly k primes (counted with multiplicity); triangle T(n,k), n>=0, 0<=k<=floor(n/2), read by rows.
Original entry on oeis.org
1, 1, 1, 1, 1, 3, 2, 5, 1, 3, 8, 5, 5, 13, 13, 1, 7, 23, 27, 7, 11, 39, 52, 25, 1, 17, 65, 99, 66, 9, 27, 106, 186, 151, 41, 1, 40, 177, 340, 323, 133, 11, 61, 293, 608, 666, 358, 61, 1, 92, 482, 1076, 1330, 867, 236, 13, 142, 781, 1894, 2581, 1971, 737, 85, 1
Offset: 0
A(5,1) = 8: [2,1,1,1], [1,2,1,1], [1,1,2,1], [1,1,1,2], [3,1,1], [1,3,1], [1,1,3], [5].
Triangle T(n,k) begins:
1;
1;
1, 1;
1, 3;
2, 5, 1;
3, 8, 5;
5, 13, 13, 1;
7, 23, 27, 7;
11, 39, 52, 25, 1;
17, 65, 99, 66, 9;
27, 106, 186, 151, 41, 1;
40, 177, 340, 323, 133, 11;
...
-
T:= proc(n) option remember; local j; if n=0 then 1
else []; for j to n do zip((x, y)->x+y, %,
[`if`(isprime(j), 0, NULL), T(n-j)], 0) od; %[] fi
end:
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]]]]; T[n_] := T[n] = Module[{j, pc}, If[n == 0, {1}, pc = {}; For[j = 1, j <= n, j++, pc = zip[Plus, pc, Join[If[PrimeQ[j], {0}, {}], T[n-j]], 0]]; pc]]; Table[T[n], {n, 0, 16}] // Flatten (* Jean-François Alcover, Jan 29 2014, after Alois P. Heinz *)
A347741
Number of compositions (ordered partitions) of n into at most 4 prime parts.
Original entry on oeis.org
1, 0, 1, 1, 1, 3, 2, 6, 6, 10, 15, 15, 24, 25, 31, 36, 35, 45, 50, 55, 63, 69, 73, 90, 91, 99, 113, 114, 130, 143, 144, 153, 166, 159, 195, 179, 213, 191, 253, 216, 279, 236, 288, 247, 343, 248, 377, 275, 397, 318, 456, 307, 503, 342, 524, 401, 572, 379, 641, 396, 667
Offset: 0
-
Table[Length@Flatten[Permutations/@IntegerPartitions[n,4,Prime@Range@PrimePi@n],1],{n,0,60}] (* Giorgos Kalogeropoulos, Sep 12 2021 *)
A347742
Number of compositions (ordered partitions) of n into at most 5 prime parts.
Original entry on oeis.org
1, 0, 1, 1, 1, 3, 2, 6, 6, 10, 16, 20, 34, 40, 56, 72, 85, 110, 120, 145, 173, 194, 228, 260, 291, 340, 383, 414, 480, 518, 579, 653, 696, 759, 835, 875, 973, 1041, 1093, 1201, 1269, 1406, 1448, 1617, 1593, 1818, 1822, 2035, 1997, 2318, 2166, 2647, 2453, 2897, 2689, 3277
Offset: 0
-
Table[Length@Flatten[Permutations/@IntegerPartitions[n,5,Prime@Range@PrimePi@n],1],{n,0,60}] (* Giorgos Kalogeropoulos, Sep 12 2021 *)
Showing 1-10 of 16 results.