cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Previous Showing 11-16 of 16 results.

A060025 Expansion of (1-x-x^N)/((1-x)(1-x^2)(1-x^3)...(1-x^N)) for N = 6.

Original entry on oeis.org

1, 0, 1, 1, 2, 2, 3, 2, 4, 3, 4, 2, 3, -1, -1, -6, -9, -17, -22, -35, -43, -61, -76, -100, -121, -155, -185, -229, -271, -328, -383, -458, -529, -622, -715, -830, -946, -1090, -1233, -1407, -1584, -1794, -2008, -2261, -2517, -2816, -3124, -3476, -3838, -4253, -4677, -5159, -5656, -6213
Offset: 0

Views

Author

N. J. A. Sloane, Mar 17 2001

Keywords

Comments

Difference of the number of partitions of n+5 into 5 parts and the number of partitions of n+5 into 6 parts. - Wesley Ivan Hurt, Apr 16 2019

Crossrefs

Cf. For other values of N: A060022 (N=3), A060023 (N=4), A060024 (N=5), this sequence (N=6), A060026 (N=7), A060027 (N=8), A060028 (N=9), A060029 (N=10).

Programs

  • Magma
    m:=6; R:=PowerSeriesRing(Integers(), 60); Coefficients(R!( (1-x-x^m)/( (&*[1-x^j: j in [1..m]]) ) )); // G. C. Greubel, Apr 17 2019
    
  • Mathematica
    With[{nn=6},CoefficientList[Series[(1-x-x^nn)/Times@@(1-x^Range[nn]),{x,0,60}],x]] (* Harvey P. Dale, May 15 2016 *)
  • PARI
    Vec((1 - x - x^6) / ((1 - x)^6*(1 + x)^3*(1 - x + x^2)*(1 + x^2)*(1 + x + x^2)^2*(1 + x + x^2 + x^3 + x^4)) + O(x^60)) \\ Colin Barker, Apr 17 2019
    
  • Sage
    m=6; ((1-x-x^m)/( product(1-x^j for j in (1..m)) )).series(x, 60).coefficients(x, sparse=False) # G. C. Greubel, Apr 17 2019

Formula

a(n) = A026811(n+5) - A026812(n+5). - Wesley Ivan Hurt, Apr 16 2019
G.f.: (1 - x - x^6) / ((1 - x)^6*(1 + x)^3*(1 - x + x^2)*(1 + x^2)*(1 + x + x^2)^2*(1 + x + x^2 + x^3 + x^4)). - Colin Barker, Apr 17 2019

A060026 Expansion of (1-x-x^N)/((1-x)(1-x^2)(1-x^3)...(1-x^N)) for N = 7.

Original entry on oeis.org

1, 0, 1, 1, 2, 2, 4, 3, 5, 5, 7, 6, 9, 6, 8, 5, 5, -1, -2, -13, -18, -33, -45, -68, -86, -121, -151, -198, -244, -310, -373, -464, -553, -671, -793, -948, -1107, -1309, -1517, -1771, -2039, -2360, -2696, -3098, -3519, -4011, -4534, -5137, -5774, -6508, -7283, -8163, -9099, -10153, -11269
Offset: 0

Views

Author

N. J. A. Sloane, Mar 17 2001

Keywords

Comments

Difference of the number of partitions of n+6 into 6 parts and the number of partitions of n+6 into 7 parts. - Wesley Ivan Hurt, Apr 16 2019

Crossrefs

Cf. For other values of N: A060022 (N=3), A060023 (N=4), A060024 (N=5), A060025 (N=6), this sequence (N=7), A060027 (N=8), A060028 (N=9), A060029 (N=10).

Programs

  • Mathematica
    With[{nn=7},CoefficientList[Series[(1-x-x^nn)/Times@@(1-x^Range[nn]),{x,0,60}],x]] (* Harvey P. Dale, May 15 2016 *)

Formula

a(n) = A026812(n+6) - A026813(n+6). - Wesley Ivan Hurt, Apr 16 2019

A211861 Number of partitions of n into parts <= 6 with the property that all parts have distinct multiplicities.

Original entry on oeis.org

1, 1, 2, 2, 4, 5, 7, 9, 12, 13, 18, 23, 25, 36, 43, 45, 60, 75, 78, 102, 108, 126, 151, 184, 188, 237, 260, 305, 339, 408, 415, 521, 548, 627, 689, 815, 824, 997, 1050, 1202, 1287, 1497, 1537, 1831, 1903, 2166, 2288, 2658, 2721, 3156, 3274
Offset: 0

Views

Author

Matthew C. Russell, Apr 25 2012

Keywords

Examples

			For n=3 the a(3)=2 partitions are {3} and {1,1,1}. Note that {2,1} does not count, as 1 and 2 appear with the same nonzero multiplicity.
		

Crossrefs

Programs

  • Haskell
    a211861 n = p 0 [] [1..6] n where
       p m ms _      0 = if m `elem` ms then 0 else 1
       p    []     _ = 0
       p m ms ks'@(k:ks) x
         | x < k       = 0
         | m == 0      = p 1 ms ks' (x - k) + p 0 ms ks x
         | m `elem` ms = p (m + 1) ms ks' (x - k)
         | otherwise   = p (m + 1) ms ks' (x - k) + p 0 (m : ms) ks x
    -- Reinhard Zumkeller, Dec 27 2012

A008641 Number of partitions of n into at most 12 parts.

Original entry on oeis.org

1, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, 56, 77, 100, 133, 172, 224, 285, 366, 460, 582, 725, 905, 1116, 1380, 1686, 2063, 2503, 3036, 3655, 4401, 5262, 6290, 7476, 8877, 10489, 12384, 14552, 17084, 19978, 23334, 27156, 31570, 36578, 42333, 48849, 56297
Offset: 0

Views

Author

Keywords

Comments

With a different offset, number of partitions of n in which the greatest part is 12.
Also number of partitions of n into parts <= 12: a(n)=A026820(n,12). [Reinhard Zumkeller, Jan 21 2010]

References

  • A. Cayley, Collected Mathematical Papers. Vols. 1-13, Cambridge Univ. Press, London, 1889-1897, Vol. 10, p. 415.
  • H. Gupta et al., Tables of Partitions. Royal Society Mathematical Tables, Vol. 4, Cambridge Univ. Press, 1958, p. 2.

Crossrefs

a(n) = A008284(n+12, 12), n >= 0.

Programs

  • Maple
    1/(1-x)/(1-x^2)/(1-x^3)/(1-x^4)/(1-x^5)/(1-x^6)/(1-x^7)/(1-x^8)/(1-x^9)/(1-x^10)/(1-x^11)/(1-x^12)
    with(combstruct):ZL13:=[S,{S=Set(Cycle(Z,card<13))}, unlabeled]:seq(count(ZL13,size=n),n=0..46); # Zerinvary Lajos, Sep 24 2007
    B:=[S,{S = Set(Sequence(Z,1 <= card),card <=12)},unlabelled]: seq(combstruct[count](B, size=n), n=0..46); # Zerinvary Lajos, Mar 21 2009
  • Mathematica
    CoefficientList[ Series[ 1/ Product[ 1 - x^n, {n, 1, 12} ], {x, 0, 60} ], x ]
    Table[ Length[ Select[ Partitions[n], First[ # ] == 12 & ]], {n, 1, 60} ]

Formula

G.f.: 1/Product_{k=1..12}(1-x^k).
a(n) = a(n-1) + a(n-2) - a(n-5) - a(n-7) + a(n-12) - a(n-13) + 2*a(n-15) + a(n-16) + a(n-17) - a(n-20) - a(n-21) - 2*a(n-22) - a(n-23) - a(n-24) - 2*a(n-26) + a(n-28) + 2*a(n-29) + 2*a(n-30) + 2*a(n-31) + 2*a(n-32) + a(n-33) + a(n-34) - a(n-36) - 2*a(n-37) - a(n-38) - 4*a(n-39) - a(n-40) - 2*a(n-41) - a(n-42) + a(n-44) + a(n-45) + 2*a(n-46) + 2a(n-47) + 2*a(n-48) + 2*a(n-49) + a(n-50) - 2*a(n-52) - a(n-54) - a(n-55) - 2*a(n-56) - a(n-57) - a(n-58) + a(n-61) + a(n-62) + 2*a(n-63) - a(n-65) + a(n-66) - a(n-71) - a(n-73) + a(n-76) + a(n-77) - a(n-78). - David Neil McGrath, Jul 28 2015

Extensions

More terms from Robert G. Wilson v, Dec 11 2000

A234666 Number of combinations for the sum of 6 different numbers from 1 to 49.

Original entry on oeis.org

1, 1, 2, 3, 5, 7, 11, 14, 20, 26, 35, 44, 58, 71, 90, 110, 136, 163, 199, 235, 282, 331, 391, 454, 532, 612, 709, 811, 931, 1057, 1206, 1360, 1540, 1729, 1945, 2172, 2432, 2702, 3009, 3331, 3692, 4070, 4494, 4935, 5426, 5940, 6506, 7097, 7748, 8423
Offset: 21

Views

Author

Jacques ALARDET, Dec 29 2013

Keywords

Examples

			a(21)=1 because the only way to sum to 21 is 1+2+3+4+5+6=21; a(279)=1 because 279 occurs only as 49+48+47+46+45+44.
		

Crossrefs

A026812 contains the same values until A026812(49)=4935.

A382864 Triangle read by rows: T(n,k) = T(n-k,k-1) + T(n-k,k) with T(0,0) = 1 for 0 <= k <= A003056(n).

Original entry on oeis.org

1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 2, 0, 1, 2, 1, 0, 1, 3, 1, 0, 1, 3, 2, 0, 1, 4, 3, 0, 1, 4, 4, 1, 0, 1, 5, 5, 1, 0, 1, 5, 7, 2, 0, 1, 6, 8, 3, 0, 1, 6, 10, 5, 0, 1, 7, 12, 6, 1, 0, 1, 7, 14, 9, 1, 0, 1, 8, 16, 11, 2, 0, 1, 8, 19, 15, 3, 0, 1, 9, 21, 18, 5, 0, 1, 9, 24, 23, 7
Offset: 0

Views

Author

Seiichi Manyama, Apr 07 2025

Keywords

Examples

			First few rows are:
  1;
  0, 1;
  0, 1;
  0, 1, 1;
  0, 1, 1;
  0, 1, 2;
  0, 1, 2,  1;
  0, 1, 3,  1;
  0, 1, 3,  2;
  0, 1, 4,  3;
  0, 1, 4,  4, 1;
  0, 1, 5,  5, 1;
  0, 1, 5,  7, 2;
  0, 1, 6,  8, 3;
  0, 1, 6, 10, 5;
  0, 1, 7, 12, 6, 1;
  ...
		

Crossrefs

Row sums give A000009.
Columns 0..10 give A000007, A000012, A004526(n-1), A069905(n-3), A026810(n-6), A026811(n-10), A026812(n-15), A026813(n-21), A026814(n-28), A026815(n-36), A026816(n-45).

Formula

G.f. of column k: x^(k*(k+1)/2) / Product_{j=1..k} (1-x^j).
T(n,k) = |A292047(n,k)| = |A292049(n,k)|.
Previous Showing 11-16 of 16 results.