A359683
Greatest positive integer whose reversed (weakly decreasing) prime indices have weighted sum (A318283) equal to n.
Original entry on oeis.org
1, 2, 3, 5, 7, 11, 14, 22, 26, 34, 44, 55, 68, 85, 110, 130, 170, 190, 242, 290, 374, 418, 506, 638, 748, 836, 1012, 1276, 1364, 1628, 1914, 2090, 2552, 3190, 3410, 4070, 4510, 5060, 6380, 7018, 8140, 9020, 9922, 11396, 14036, 15004, 17908, 19844, 21692, 23452
Offset: 0
The terms together with their prime indices begin:
1: {}
2: {1}
3: {2}
5: {3}
7: {4}
11: {5}
14: {1,4}
22: {1,5}
26: {1,6}
34: {1,7}
44: {1,1,5}
55: {3,5}
68: {1,1,7}
85: {3,7}
110: {1,3,5}
130: {1,3,6}
170: {1,3,7}
190: {1,3,8}
242: {1,5,5}
290: {1,3,10}
The 6 numbers with weighted sum of reversed prime indices 9, together with their prime indices:
18: {1,2,2}
23: {9}
25: {3,3}
28: {1,1,4}
33: {2,5}
34: {1,7}
Hence a(9) = 34.
-
nn=10;
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
ots[y_]:=Sum[i*y[[i]],{i,Length[y]}];
seq=Table[ots[Reverse[primeMS[n]]],{n,1,2^nn}];
Table[Position[seq,k][[-1,1]],{k,0,nn}]
A359754
Positions of first appearances in the sequence of weighted sums of reversed prime indices (A318283).
Original entry on oeis.org
1, 2, 3, 4, 6, 8, 10, 12, 16, 18, 19, 24, 27, 32, 36, 43, 48, 59, 61, 64, 67, 71, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269
Offset: 1
The terms together with their prime indices begin:
1: {}
2: {1}
3: {2}
4: {1,1}
6: {1,2}
8: {1,1,1}
10: {1,3}
12: {1,1,2}
16: {1,1,1,1}
18: {1,2,2}
19: {8}
24: {1,1,1,2}
27: {2,2,2}
32: {1,1,1,1,1}
36: {1,1,2,2}
43: {14}
48: {1,1,1,1,2}
This is the sorted version of
A359679.
A053632 counts compositions by weighted sum.
-
nn=100;
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
ots[y_]:=Sum[i*y[[i]],{i,Length[y]}];
seq=Table[ots[Reverse[primeMS[n]]],{n,1,nn}];
Select[Range[nn],FreeQ[seq[[Range[#-1]]],seq[[#]]]&]
A363620
Reverse-weighted alternating sum of the multiset of prime indices of n.
Original entry on oeis.org
0, 1, 2, 1, 3, 0, 4, 2, 2, -1, 5, 3, 6, -2, 1, 2, 7, 1, 8, 4, 0, -3, 9, 1, 3, -4, 4, 5, 10, 2, 11, 3, -1, -5, 2, 3, 12, -6, -2, 0, 13, 3, 14, 6, 5, -7, 15, 4, 4, 0, -3, 7, 16, 0, 1, -1, -4, -8, 17, 2, 18, -9, 6, 3, 0, 4, 19, 8, -5, 1, 20, 2, 21, -10, 3, 9, 3
Offset: 1
The prime indices of 300 are {1,1,2,3,3}, with reverse-weighted alternating sum 1*3 - 2*3 + 3*2 - 4*1 + 5*1 = 4, so a(300) = 4.
Cf.
A001221,
A046660,
A053632,
A106529,
A124010,
A222855,
A261079,
A358137,
A359674,
A359755,
A363531,
A363532.
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prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
revaltwtsum[y_]:=Sum[(-1)^(Length[y]-k)*k*y[[-k]],{k,1,Length[y]}];
Table[revaltwtsum[prix[n]],{n,100}]
A363624
Weighted alternating sum of the integer partition with Heinz number n.
Original entry on oeis.org
0, 1, 2, -1, 3, 0, 4, 2, -2, 1, 5, 3, 6, 2, -1, -2, 7, 1, 8, 4, 0, 3, 9, -1, -3, 4, 4, 5, 10, 2, 11, 3, 1, 5, -2, -3, 12, 6, 2, 0, 13, 3, 14, 6, 5, 7, 15, 4, -4, 0, 3, 7, 16, 0, -1, 1, 4, 8, 17, -2, 18, 9, 6, -3, 0, 4, 19, 8, 5, 1, 20, 2, 21, 10, 3, 9, -3, 5
Offset: 1
The partition with Heinz number 600 is (3,3,2,1,1,1), with weighted alternating sum 1*3 - 2*3 + 3*2 - 4*1 + 5*1 - 6*1 = -2, so a(600) = -2.
For multisets instead of partitions we have
A363619.
A359677 gives zero-based weighted sum of prime indices, reverse
A359674.
A363626 counts compositions with reverse-weighted alternating sum 0.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n], {p_,k_}:>Table[PrimePi[p],{k}]]]];
altwtsum[y_]:=Sum[(-1)^(k-1)*k*y[[k]],{k,1,Length[y]}];
Table[altwtsum[Reverse[prix[n]]],{n,100}]
A363625
Reverse-weighted alternating sum of the integer partition with Heinz number n.
Original entry on oeis.org
0, 1, 2, 1, 3, 3, 4, 2, 2, 5, 5, 5, 6, 7, 4, 2, 7, 3, 8, 8, 6, 9, 9, 6, 3, 11, 4, 11, 10, 6, 11, 3, 8, 13, 5, 3, 12, 15, 10, 10, 13, 9, 14, 14, 7, 17, 15, 8, 4, 4, 12, 17, 16, 5, 7, 14, 14, 19, 17, 7, 18, 21, 10, 3, 9, 12, 19, 20, 16, 7, 20, 4, 21, 23, 5, 23
Offset: 1
The partition with Heinz number 600 is (3,3,2,1,1,1), so a(600) = -1*1 + 2*1 - 3*1 + 4*2 - 5*3 + 6*3 = 9.
For multisets instead of partitions we have
A363620.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
revaltwtsum[y_]:=Sum[(-1)^(Length[y]-k)*k*y[[-k]],{k,1,Length[y]}];
Table[revaltwtsum[Reverse[prix[n]]],{n,100}]
A363531
Heinz numbers of integer partitions such that 3*(sum) = (reverse-weighted sum).
Original entry on oeis.org
1, 32, 144, 216, 243, 672, 1008, 1350, 2176, 2250, 2520, 2673, 3125, 3969, 4160, 4200, 5940, 6240, 6615, 7344, 7424, 7744, 8262, 9261, 9800, 9900, 10400, 11616, 12250, 12312, 12375, 13104, 13720, 14720, 14742, 16767, 16807, 17150, 19360, 21840, 22080, 23100
Offset: 1
The terms together with their prime indices begin:
1: {}
32: {1,1,1,1,1}
144: {1,1,1,1,2,2}
216: {1,1,1,2,2,2}
243: {2,2,2,2,2}
672: {1,1,1,1,1,2,4}
1008: {1,1,1,1,2,2,4}
1350: {1,2,2,2,3,3}
2176: {1,1,1,1,1,1,1,7}
2250: {1,2,2,3,3,3}
2520: {1,1,1,2,2,3,4}
2673: {2,2,2,2,2,5}
3125: {3,3,3,3,3}
3969: {2,2,2,2,4,4}
4160: {1,1,1,1,1,1,3,6}
These partitions are counted by
A363526.
A053632 counts compositions by weighted sum.
A318283 gives weighted sum of reversed prime indices, row-sums of
A358136.
Cf.
A000041,
A000720,
A001221,
A046660,
A106529,
A118914,
A124010,
A181819,
A215366,
A359362,
A359755.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[1000],3*Total[prix[#]]==Total[Accumulate[prix[#]]]&]
A363526
Number of integer partitions of n with reverse-weighted sum 3*n.
Original entry on oeis.org
1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 4, 3, 2, 4, 4, 4, 5, 5, 4, 7, 7, 5, 8, 7, 6, 11, 9, 8, 11, 10, 10, 13, 12, 11, 15, 15, 12, 17, 16, 14, 20, 18, 16, 22, 20, 19, 24, 22, 20, 27, 26, 23, 29, 27, 25, 33, 30, 28, 35, 33, 31, 38, 36, 33, 41, 40
Offset: 0
The partition (6,4,4,1) has sum 15 and reverse-weighted sum 45 so is counted under a(15).
The a(n) partitions for n = {5, 10, 15, 16, 21, 24}:
(1,1,1,1,1) (4,3,2,1) (6,4,4,1) (6,5,4,1) (8,6,6,1) (9,7,7,1)
(2,2,2,2,2) (6,5,2,2) (6,6,2,2) (8,7,4,2) (9,8,5,2)
(7,3,3,2) (7,4,3,2) (9,5,5,2) (9,9,3,3)
(3,3,3,3,3) (9,6,3,3) (10,6,6,2)
(10,4,4,3) (10,7,4,3)
(11,5,5,3)
(12,4,4,4)
Positions of terms with omega > 4 appear to be
A079998.
The version for compositions is
A231429.
The non-reverse version is
A363527.
A318283 gives weighted sum of reversed prime indices, row-sums of
A358136.
Cf.
A000016,
A008284,
A067538,
A222855,
A222970,
A359755,
A360672,
A360675,
A362559,
A362560,
A363525,
A363528.
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Table[Length[Select[IntegerPartitions[n],Total[Accumulate[#]]==3n&]],{n,0,30}]
A363527
Number of integer partitions of n with weighted sum 3*n.
Original entry on oeis.org
1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 3, 4, 4, 6, 8, 7, 10, 13, 13, 21, 25, 24, 37, 39, 40, 58, 63, 72, 94, 106, 118, 144, 165, 181, 224, 256, 277, 341, 387, 417, 504, 560, 615, 743, 818, 899, 1066, 1171, 1285, 1502, 1655, 1819, 2108, 2315, 2547, 2915
Offset: 0
The partition (2,2,1,1,1,1) has sum 8 and weighted sum 24 so is counted under a(8).
The a(13) = 1 through a(18) = 8 partitions:
(332221) (333221) (33333) (442222) (443222) (443331)
(4322111) (522222) (5322211) (4433111) (444222)
(71111111) (4332111) (55111111) (5332211) (533322)
(63111111) (63211111) (55211111) (4443111)
(63311111) (7222221)
(72221111) (55311111)
(64221111)
(A11111111)
The version for compositions is
A231429.
These partitions have ranks
A363531.
A318283 gives weighted sum of reversed prime indices, row-sums of
A358136.
Cf.
A000016,
A008284,
A067538,
A222855,
A222970,
A359755,
A360672,
A360675,
A362559,
A362560,
A363525,
A363528,
A363532.
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Table[Length[Select[IntegerPartitions[n],Total[Accumulate[Reverse[#]]]==3n&]],{n,0,30}]
A363530
Heinz numbers of integer partitions such that 3*(sum) = (weighted sum).
Original entry on oeis.org
1, 32, 40, 60, 100, 126, 210, 243, 294, 351, 550, 585, 770, 819, 1210, 1274, 1275, 1287, 1521, 1785, 2002, 2366, 2793, 2805, 2875, 3125, 3315, 4025, 4114, 4335, 4389, 4862, 5187, 6325, 6358, 6422, 6783, 7105, 7475, 7581, 8349, 8398, 9386, 9775, 9867, 10925
Offset: 1
The terms together with their prime indices begin:
1: {}
32: {1,1,1,1,1}
40: {1,1,1,3}
60: {1,1,2,3}
100: {1,1,3,3}
126: {1,2,2,4}
210: {1,2,3,4}
243: {2,2,2,2,2}
294: {1,2,4,4}
351: {2,2,2,6}
550: {1,3,3,5}
585: {2,2,3,6}
770: {1,3,4,5}
819: {2,2,4,6}
These partitions are counted by
A363527.
A053632 counts compositions by weighted sum.
A318283 gives weighted sum of reversed prime indices, row-sums of
A358136.
Cf.
A000041,
A000720,
A001221,
A046660,
A106529,
A118914,
A124010,
A181819,
A215366,
A359362,
A359755.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[1000],3*Total[prix[#]]==Total[Accumulate[Reverse[prix[#]]]]&]
A363525
Number of integer partitions of n with weighted sum divisible by reverse-weighted sum.
Original entry on oeis.org
1, 2, 2, 3, 2, 4, 2, 4, 5, 5, 3, 10, 4, 7, 13, 10, 8, 29, 10, 18, 39, 20, 20, 70, 29, 40, 105, 65, 55, 166, 73, 132, 242, 141, 129, 476, 183, 248, 580, 487, 312, 984, 422, 868, 1345, 825, 724, 2709, 949, 1505, 2756, 2902, 1611, 4664, 2289, 4942, 5828, 4278
Offset: 1
The partition (6,5,4,3,2,1,1,1,1) has weighted sum 80, reverse 160, so is counted under a(24).
The a(n) partitions for n = 1, 2, 4, 6, 9, 12, 14 (A..E = 10-14):
1 2 4 6 9 C E
11 22 33 333 66 77
1111 222 711 444 65111
111111 6111 921 73211
111111111 3333 2222222
7311 71111111
63111 11111111111111
222222
621111
111111111111
The case of equality (and reciprocal version) is
A000005.
A318283 gives weighted sum of reversed prime indices, row-sums of
A358136.
Cf.
A000016,
A008284,
A067538,
A222855,
A222970,
A358137,
A359755,
A362558,
A362559,
A362560,
A363527.
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Table[Length[Select[IntegerPartitions[n], Divisible[Total[Accumulate[#]], Total[Accumulate[Reverse[#]]]]&]],{n,30}]
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