A010055 -id:A010055 - cp's OEIS frontend

A341125 Number of partitions of n into 7 prime powers (including 1).

1, 1, 2, 3, 5, 6, 10, 13, 18, 22, 30, 35, 47, 54, 68, 78, 97, 107, 132, 146, 173, 190, 225, 242, 285, 305, 352, 377, 434, 456, 525, 553, 627, 659, 748, 778, 881, 916, 1028, 1068, 1197, 1232, 1381, 1421, 1578, 1619, 1801, 1837, 2041, 2079, 2296, 2337, 2583, 2613

Offset: 7

Ilya Gutkovskiy, Feb 05 2021

nonn

Cf. A000961, A010055, A071330, A341112, A341122, A341123, A341124, A341126, A341127.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
      `if`(q(i), b(n-i, min(n-i, i), t-1), 0)))
    end:
a:= n-> b(n$2, 7):
seq(a(n), n=7..60);  # Alois P. Heinz, Feb 05 2021

q[n_] := q[n] = Length[FactorInteger[n]] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
     If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
     If[q[i], b[n - i, Min[n - i, i], t - 1], 0]]];
a[n_] := b[n, n, 7];
Table[a[n], {n, 7, 60}] (* Jean-François Alcover, Feb 22 2022, after Alois P. Heinz *)

A341126 Number of partitions of n into 8 prime powers (including 1).

Original entry on oeis.org

1, 1, 2, 3, 5, 6, 10, 13, 19, 23, 32, 38, 51, 60, 77, 90, 113, 128, 158, 179, 215, 240, 287, 316, 373, 409, 475, 517, 599, 645, 741, 799, 908, 971, 1104, 1173, 1326, 1408, 1580, 1670, 1874, 1967, 2198, 2310, 2563, 2680, 2976, 3097, 3426, 3566, 3926, 4070, 4485

Offset: 8

Ilya Gutkovskiy, Feb 05 2021

nonn

Cf. A000961, A010055, A071330, A341112, A341122, A341123, A341124, A341125, A341127.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
      `if`(q(i), b(n-i, min(n-i, i), t-1), 0)))
    end:
a:= n-> b(n$2, 8):
seq(a(n), n=8..60);  # Alois P. Heinz, Feb 05 2021

q[n_] := q[n] = Length[FactorInteger[n]] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
     If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
     If[q[i], b[n - i, Min[n - i, i], t - 1], 0]]];
a[n_] := b[n, n, 8];
Table[a[n], {n, 8, 60}] (* Jean-François Alcover, Feb 22 2022, after _Alois P. Heinz *)

A341127 Number of partitions of n into 9 prime powers (including 1).

Original entry on oeis.org

1, 1, 2, 3, 5, 6, 10, 13, 19, 24, 33, 40, 54, 64, 83, 99, 125, 144, 180, 206, 250, 284, 341, 383, 455, 506, 593, 656, 762, 835, 965, 1054, 1206, 1309, 1491, 1610, 1825, 1964, 2213, 2374, 2664, 2843, 3179, 3387, 3769, 3998, 4440, 4695, 5194, 5480, 6043, 6357

Offset: 9

Ilya Gutkovskiy, Feb 05 2021

nonn

Cf. A000961, A010055, A071330, A341112, A341122, A341123, A341124, A341125, A341126.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
      `if`(q(i), b(n-i, min(n-i, i), t-1), 0)))
    end:
a:= n-> b(n$2, 9):
seq(a(n), n=9..60);  # Alois P. Heinz, Feb 05 2021

q[n_] := q[n] = Length[FactorInteger[n]] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
     If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
     If[q[i], b[n - i, Min[n - i, i], t - 1], 0]]];
a[n_] := b[n, n, 9];
Table[a[n], {n, 9, 60}] (* Jean-François Alcover, Feb 22 2022, after Alois P. Heinz *)

A341140 Number of partitions of n into 3 distinct prime powers (including 1).

Original entry on oeis.org

1, 1, 2, 2, 3, 3, 5, 5, 7, 6, 8, 7, 8, 8, 10, 10, 12, 11, 12, 12, 13, 12, 16, 15, 15, 16, 18, 17, 19, 20, 21, 24, 22, 22, 23, 25, 22, 27, 26, 25, 26, 29, 25, 31, 27, 30, 31, 34, 26, 34, 31, 35, 32, 38, 29, 40, 32, 36, 34, 41, 29, 44, 35, 41, 36, 47, 34, 51, 38, 45, 41, 54

Offset: 6

Ilya Gutkovskiy, Feb 05 2021

nonn

Cf. A000961, A010055, A282064, A307727, A307825, A341112, A341132, A341141, A341142, A341143, A341144, A341145.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
      `if`(q(i), b(n-i, min(n-i, i-1), t-1), 0)))
    end:
a:= n-> b(n$2, 3):
seq(a(n), n=6..77);  # Alois P. Heinz, Feb 05 2021

q[n_] := q[n] = PrimeNu[n] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
     If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
     If[q[i], b[n - i, Min[n - i, i - 1], t - 1], 0]]];
a[n_] := b[n, n, 3];
Table[a[n], {n, 6, 77}] (* Jean-François Alcover, Jul 13 2021, after Alois P. Heinz *)

A341141 Number of partitions of n into 4 distinct prime powers (including 1).

Original entry on oeis.org

1, 1, 1, 2, 3, 4, 5, 7, 7, 9, 9, 11, 12, 15, 15, 19, 18, 21, 21, 26, 25, 30, 29, 35, 32, 39, 37, 45, 43, 52, 50, 58, 54, 62, 61, 71, 66, 75, 74, 81, 78, 89, 85, 96, 93, 102, 99, 110, 103, 115, 117, 122, 120, 131, 127, 136, 136, 139, 142, 153, 147, 154, 160, 163, 165, 177, 175

Offset: 10

Ilya Gutkovskiy, Feb 05 2021

nonn

Cf. A000961, A010055, A341122, A341132, A341133, A341140, A341142, A341143, A341144, A341145.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
      `if`(q(i), b(n-i, min(n-i, i-1), t-1), 0)))
    end:
a:= n-> b(n$2, 4):
seq(a(n), n=10..76);  # Alois P. Heinz, Feb 05 2021

q[n_] := q[n] = PrimeNu[n] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
     If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
     If[q[i], b[n - i, Min[n - i, i - 1], t - 1], 0]]];
a[n_] := b[n, n, 4];
Table[a[n], {n, 10, 76}] (* Jean-François Alcover, Jul 13 2021, after Alois P. Heinz *)

A341142 Number of partitions of n into 5 distinct prime powers (including 1).

Original entry on oeis.org

1, 0, 1, 2, 3, 3, 5, 5, 7, 8, 10, 12, 15, 15, 18, 21, 23, 26, 31, 33, 36, 41, 43, 48, 52, 58, 62, 72, 72, 82, 85, 95, 97, 112, 112, 125, 127, 142, 142, 161, 159, 181, 180, 200, 196, 222, 217, 243, 239, 269, 261, 291, 284, 316, 308, 341, 332, 370, 358, 394, 381, 427, 414, 456

Offset: 15

Ilya Gutkovskiy, Feb 05 2021

nonn

Alois P. Heinz, Table of n, a(n) for n = 15..5000

Cf. A000961, A010055, A341123, A341132, A341134, A341140, A341141, A341143, A341144, A341145.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
      `if`(q(i), b(n-i, min(n-i, i-1), t-1), 0)))
    end:
a:= n-> b(n$2, 5):
seq(a(n), n=15..78);  # Alois P. Heinz, Feb 05 2021

q[n_] := q[n] = PrimeNu[n] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
     If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
     If[q[i], b[n - i, Min[n - i, i - 1], t - 1], 0]]];
a[n_] := b[n, n, 5];
Table[a[n], {n, 15, 78}] (* Jean-François Alcover, Jul 13 2021, after Alois P. Heinz *)
Table[Count[IntegerPartitions[n,{5}],?(Max[PrimeNu[#]]<2&&Length[#]==Length[Union[#]]&)],{n,15,80}] (* _Harvey P. Dale, Dec 22 2024 *)

A071140 Numbers n such that sum of distinct primes dividing n is divisible by largest prime dividing n; n is neither a prime, nor a true power of prime.

Original entry on oeis.org

30, 60, 70, 90, 120, 140, 150, 180, 240, 270, 280, 286, 300, 350, 360, 450, 480, 490, 540, 560, 572, 600, 646, 700, 720, 750, 810, 900, 960, 980, 1080, 1120, 1144, 1200, 1292, 1350, 1400, 1440, 1500, 1620, 1750, 1798, 1800, 1920, 1960, 2160, 2240, 2250

Offset: 1

Labos Elemer, May 13 2002

nonn

a(n) are the numbers such that the difference between the largest and the smallest prime divisor equals the sum of the other distinct prime divisors. - Michel Lagneau, Nov 13 2011
The statement above is only true for 966 of the first 1000 terms. The first counterexample is a(140) = 15015. - Donovan Johnson, Apr 10 2013
Lagneau's definition can be simplified to the largest prime divisor equals the sum of the other distinct prime divisors. - Christian N. K. Anderson, Apr 15 2013

			n = 70 = 2*5*7 has a form of 2pq, where p and q are twin primes; n = 3135 = 3*5*11*19, sum = 3+5+11+19 = 38 = 2*19, divisible by 19.

Donovan Johnson, Table of n, a(n) for n = 1..1000

Cf. A008472, A006530, A000961, A025475, A037074, A071139-A071147.

Subsequence of A024619.

a071140 n = a071140_list !! (n-1)
a071140_list = filter (\x -> a008472 x `mod` a006530 x == 0) a024619_list
-- Reinhard Zumkeller, Apr 18 2013

ffi[x_] := Flatten[FactorInteger[x]] lf[x_] := Length[FactorInteger[x]] ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}] sb[x_] := Apply[Plus, ba[x]] ma[x_] := Part[Reverse[Flatten[FactorInteger[x]]], 2] Do[s=sb[n]/ma[n]; If[IntegerQ[s]&&Greater[s, 1], Print[{n, ba[n]}]], {n, 2, 1000000}]
(* Second program: *)
Select[Range@ 2250, And[Length@ # > 1, Divisible[Total@ #, Last@ #]] &[FactorInteger[#][[All, 1]] ] &] (* Michael De Vlieger, Jul 18 2017 *)

A008472(n)/A006530(n) is an integer and n has at least 3 distinct prime factors.

A008472(a(n)) mod A006530(a(n)) = 0 and A010055(a(n)) = 0. - Reinhard Zumkeller, Apr 18 2013

A223491 Largest Fermi-Dirac factor of n.

Original entry on oeis.org

1, 2, 3, 4, 5, 3, 7, 4, 9, 5, 11, 4, 13, 7, 5, 16, 17, 9, 19, 5, 7, 11, 23, 4, 25, 13, 9, 7, 29, 5, 31, 16, 11, 17, 7, 9, 37, 19, 13, 5, 41, 7, 43, 11, 9, 23, 47, 16, 49, 25, 17, 13, 53, 9, 11, 7, 19, 29, 59, 5, 61, 31, 9, 16, 13, 11, 67, 17, 23, 7, 71, 9

Offset: 1

Reinhard Zumkeller, Mar 20 2013

nonn

Greatest Fermi-Dirac factor of n: Largest divisor of n of the form p^(2^k), for some prime p and k >= 0, with a(1) = 1. Thus for n > 1, the largest term of A050376 that divides n. - Antti Karttunen, Apr 13 2018

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
OEIS Wiki, "Fermi-Dirac representation" of n

Cf. A223490, A050376, A034699, A000040 (subsequence), A302776, A302785, A302789 (ordinal transform).

Cf. also A006530, A034699.

Haskell
```
a223491 = last . a213925_row
```

f[p_, e_] := p^(2^Floor[Log2[e]]); a[n_] := Max @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Nov 26 2020 *)

ispow2(n) = (n && !bitand(n,n-1));
A223491(n) = if(1==n,n,fordiv(n, d, if(ispow2(isprimepower(n/d)), return(n/d)))); \\ Antti Karttunen, Apr 13 2018

a(n) = A213925(n,A064547(n)).
A209229(A100995(a(n))) = 1; A010055(a(n)) = 1.
From Antti Karttunen, Apr 13 2018: (Start)
a(1) = 1; for n > 1, a(n) = A050376(A302785(n)).
a(n) = n/A302776(n).
(End)

A341133 Number of ways to write n as an ordered sum of 4 prime powers (including 1).

Original entry on oeis.org

1, 4, 10, 20, 35, 52, 72, 96, 125, 156, 196, 236, 277, 316, 362, 400, 451, 496, 554, 604, 668, 704, 770, 808, 871, 920, 1014, 1040, 1131, 1172, 1266, 1308, 1449, 1484, 1638, 1672, 1802, 1820, 1992, 1964, 2167, 2172, 2332, 2296, 2534, 2444, 2698, 2648, 2889, 2820, 3140

Offset: 4

Ilya Gutkovskiy, Feb 05 2021

nonn

Cf. A000961, A010055, A282062, A282064, A341122, A341134, A341135, A341136, A341137, A341138, A341139.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 4):
seq(a(n), n=4..54);  # Alois P. Heinz, Feb 05 2021

nmax = 54; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^4, {x, 0, nmax}], x] // Drop[#, 4] &

A341134 Number of ways to write n as an ordered sum of 5 prime powers (including 1).

Original entry on oeis.org

1, 5, 15, 35, 70, 121, 190, 280, 395, 535, 711, 920, 1160, 1425, 1725, 2041, 2395, 2775, 3200, 3645, 4146, 4640, 5190, 5730, 6325, 6915, 7625, 8270, 9030, 9745, 10576, 11320, 12320, 13185, 14305, 15281, 16510, 17480, 18855, 19835, 21306, 22435, 24010, 25025, 26810, 27790, 29590

Offset: 5

Ilya Gutkovskiy, Feb 05 2021

nonn

Cf. A000961, A010055, A282062, A282064, A341123, A341133, A341135, A341136, A341137, A341138, A341139.

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 5):
seq(a(n), n=5..51);  # Alois P. Heinz, Feb 05 2021

nmax = 51; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^5, {x, 0, nmax}], x] // Drop[#, 5] &

cp's OEIS Frontend

A341125 Number of partitions of n into 7 prime powers (including 1).

Views

Author

Keywords

Crossrefs

Programs

Maple

Mathematica

A341126 Number of partitions of n into 8 prime powers (including 1).

Views

Author

Keywords

Crossrefs

Programs

Maple

Mathematica

A341127 Number of partitions of n into 9 prime powers (including 1).

Views

Author

Keywords

Crossrefs

Programs

Maple

Mathematica

A341140 Number of partitions of n into 3 distinct prime powers (including 1).

Views

Author

Keywords

Crossrefs

Programs

Maple

Mathematica

A341141 Number of partitions of n into 4 distinct prime powers (including 1).

Views

Author

Keywords

Crossrefs

Programs

Maple

Mathematica

A341142 Number of partitions of n into 5 distinct prime powers (including 1).

Views

Author

Keywords

Links

Crossrefs

Programs

Maple

Mathematica

A071140 Numbers n such that sum of distinct primes dividing n is divisible by largest prime dividing n; n is neither a prime, nor a true power of prime.

Views

Author

Keywords

Comments

Examples

Links

Crossrefs

Programs

Haskell

Mathematica

Formula

A223491 Largest Fermi-Dirac factor of n.

Views

Author

Keywords

Comments

Links

Crossrefs

Programs

Haskell

Mathematica

PARI

Formula

A341133 Number of ways to write n as an ordered sum of 4 prime powers (including 1).

Views

Author

Keywords

Crossrefs

Programs