A330351
Expansion of e.g.f. -Sum_{k>=1} log(1 - (exp(x) - 1)^k) / k.
Original entry on oeis.org
1, 3, 11, 57, 359, 2793, 25871, 273297, 3268199, 44132313, 659178431, 10710083937, 189256343639, 3636935896233, 75228664345391, 1657133255788977, 38770903634692679, 964609458391250553, 25470259163197390751, 709595190213796188417
Offset: 1
Cf.
A000005,
A000629,
A002746,
A008277,
A028342,
A308554,
A318249,
A330352,
A330353,
A330354,
A330445.
-
nmax = 20; CoefficientList[Series[-Sum[Log[1 - (Exp[x] - 1)^k]/k, {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]! // Rest
Table[Sum[StirlingS2[n, k] (k - 1)! DivisorSigma[0, k], {k, 1, n}], {n, 1, 20}]
A351762
Expansion of e.g.f. 1/(1 - 2*x*exp(x)).
Original entry on oeis.org
1, 2, 12, 102, 1160, 16490, 281292, 5598110, 127326096, 3257961426, 92625793940, 2896747456262, 98827517418456, 3652643136982970, 145385563800940764, 6200097935648462190, 282035994269804870432, 13631368700936950044578, 697586352315912913754916
Offset: 0
-
my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1-2*x*exp(x))))
-
a(n) = n!*sum(k=0, n, 2^(n-k)*(n-k)^k/k!);
-
a(n) = if(n==0, 1, 2*n*sum(k=0, n-1, binomial(n-1, k)*a(k)));
A154693
Triangle read by rows: T(n, k) = (2^(n-k) + 2^k)*A008292(n+1, k+1).
Original entry on oeis.org
2, 3, 3, 5, 16, 5, 9, 66, 66, 9, 17, 260, 528, 260, 17, 33, 1026, 3624, 3624, 1026, 33, 65, 4080, 23820, 38656, 23820, 4080, 65, 129, 16302, 154548, 374856, 374856, 154548, 16302, 129, 257, 65260, 993344, 3529360, 4998080, 3529360, 993344, 65260, 257
Offset: 0
The triangle begins as:
2;
3, 3;
5, 16, 5;
9, 66, 66, 9;
17, 260, 528, 260, 17;
33, 1026, 3624, 3624, 1026, 33;
65, 4080, 23820, 38656, 23820, 4080, 65;
129, 16302, 154548, 374856, 374856, 154548, 16302, 129;
257, 65260, 993344, 3529360, 4998080, 3529360, 993344, 65260, 257;
- G. C. Greubel, Rows n = 0..50 of the triangle, flattened
- A. Lakhtakia, R. Messier, V. K. Varadan, and V. V. Varadan, Use of combinatorial algebra for diffusion on fractals, Physical Review A, volume 34, Number 3 (1986) p. 2501, (FIG. 3)
-
A154693:= func< n,k | (2^(n-k) + 2^k)*EulerianNumber(n+1, k) >;
[A154693(n,k): k in [0..n], n in [0..10]]; // G. C. Greubel, Jan 17 2025
-
p=2; q=1;
A008292[n_,k_]:= A008292[n,k]= Sum[(-1)^j*(k-j)^n*Binomial[n+1,j], {j,0,k}];
T[n_, m_]:= (p^(n-m)*q^m + p^m*q^(n-m))*A008292[n+1,m+1];
Table[T[n, m], {n,0,12}, {m,0,n}]//Flatten
-
from sage.combinat.combinat import eulerian_number
def A154693(n,k): return (2^(n-k) +2^k)*eulerian_number(n+1,k)
print(flatten([[A154693(n,k) for k in range(n+1)] for n in range(13)])) # G. C. Greubel, Jan 17 2025
Definition simplified by the Assoc. Eds. of the OEIS - Aug 08 2010.
A302923
Raw half-moments of a Fibonacci-geometric probability distribution.
Original entry on oeis.org
3, 29, 411, 7757, 183003, 5180909, 171119931, 6459325517, 274300290843, 12942639522989, 671756887456251, 38035572830424077, 2333081451314129883, 154118411443366428269, 10907930704590567517371, 823491157770358707135437, 66054810199299268861908123
Offset: 1
a(1)=3 is half the first raw moment of the distribution. It is half the arithmetic average of integers following the distribution.
a(2)=29 is half the second raw moment. It is half the arithmetic average of the squares of integers following the distribution.
-
Module[{max, r, g, rawMoments},
max = 17;
r = Range[0, max];
g[x_] := x^2/(4 - 2 x - x^2);
rawMoments = r! CoefficientList[Normal[Series[g[Exp[x]], {x, 0, max}]], x];
Rest[rawMoments]/2
]
A302924
Central moments of a Fibonacci-geometric probability distribution.
Original entry on oeis.org
1, 0, 22, 210, 4426, 102330, 2906362, 95952570, 3622138906, 153816150810, 7257695358202, 376693381614330, 21328770664314586, 1308295248437904090, 86423208789970618042, 6116714829331037666490, 461779664078480243085466, 37040796099362864616022170
Offset: 0
a(0)=1 is the 0th central moment of the distribution, which is the total probability.
a(1)=0 is the 1st central moment, or the "mean about the mean". It is zero by definition of central moments.
a(2)=22 is the 2nd central moment, known as the variance or the square of the standard deviation. It measures how far integers following the distribution are from the mean by averaging the squares of their differences from the mean.
-
Module[{max, r, g, moments},
max = 17;
r = Range[0, max];
g[x_] := x^2/(4 - 2 x - x^2);
moments = r! CoefficientList[Normal[Series[g[Exp[x]], {x, 0, max}]], x];
Table[Sum[Binomial[n, k] moments[[k + 1]] (-6)^(n - k), {k, 0, n}], {n, 0, max}]
]
A302925
Central half-moments of a Fibonacci-geometric probability distribution.
Original entry on oeis.org
0, 11, 105, 2213, 51165, 1453181, 47976285, 1811069453, 76908075405, 3628847679101, 188346690807165, 10664385332157293, 654147624218952045, 43211604394985309021, 3058357414665518833245, 230889832039240121542733, 18520398049681432308011085
Offset: 1
a(1)=0 is half the 1st central moment of the distribution, or half the "mean about the mean". It is zero by definition of central moments.
a(2)=11 is half the 2nd central moment, or half the variance, or half the square of the standard deviation.
-
Module[{max, r, g, moments, centralMoments},
max = 17;
r = Range[0, max];
g[x_] := x^2/(4 - 2 x - x^2);
moments = r! CoefficientList[Normal[Series[g[Exp[x]], {x, 0, max}]], x];
centralMoments = Table[Sum[Binomial[n, k] moments[[k + 1]] (-6)^(n - k), {k, 0, n}], {n, 0, max}];
Rest[centralMoments]/2
]
A302926
Cumulants of a Fibonacci-geometric probability distribution.
Original entry on oeis.org
0, 6, 22, 210, 2974, 56130, 1324222, 37489410, 1238235454, 46740118530, 1984855550782, 93653819396610, 4860878501987134, 275227990564092930, 16882335978752910142, 1115211301788480951810, 78930528072274523870014, 5958837996496319756259330
Offset: 0
a(0)=0 is the 0th cumulant of the distribution. The 0th cumulant is always zero.
a(1)=6 is the 1st cumulant, which is always the mean.
a(2)=22 is the 2nd cumulant, which is always the variance.
-
Module[{max, r, g},
max = 17;
r = Range[0, max];
g[x_] := x^2/(4 - 2 x - x^2);
r! CoefficientList[Normal[Series[Log[g[Exp[x]]], {x, 0, max}]], x]
]
A302927
Half-cumulants of a Fibonacci-geometric probability distribution.
Original entry on oeis.org
0, 3, 11, 105, 1487, 28065, 662111, 18744705, 619117727, 23370059265, 992427775391, 46826909698305, 2430439250993567, 137613995282046465, 8441167989376455071, 557605650894240475905, 39465264036137261935007, 2979418998248159878129665
Offset: 0
a(0)=0 is half the 0th cumulant of the distribution. The 0th cumulant is always zero.
a(1)=3 is half the 1st cumulant, which is half the mean.
a(2)=11 is half the 2nd cumulant, which is half the variance.
-
Module[{max, r, g},
max = 17;
r = Range[0, max];
g[x_] := x^2/(4 - 2 x - x^2);
(1/2) r! CoefficientList[Normal[Series[Log[g[Exp[x]]], {x, 0, max}]], x]
]
-
concat(0, Vec(serlaplace(log(exp(2*x)/(4-2*exp(x)-exp(2*x))))/2)) \\ Michel Marcus, Apr 17 2018
A005463
Number of simplices in barycentric subdivision of n-simplex.
Original entry on oeis.org
1, 63, 1932, 46620, 1020600, 21538440, 451725120, 9574044480, 207048441600, 4595022432000, 105006251750400, 2475732702643200, 60284572969420800, 1516762345722624000, 39433286715863040000, 1059143615076298752000, 29378569022287220736000, 841159994641469927424000
Offset: 4
- R. Austin, R. K. Guy, and R. Nowakowski, unpublished notes, circa 1987.
- R. K. Guy, personal communication.
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
- G. C. Greubel, Table of n, a(n) for n = 4..440
- R. Austin, R. K. Guy, and R. Nowakowski, Unpublished notes, 1987
- Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
- Rajesh Kumar Mohapatra and Tzung-Pei Hong, On the Number of Finite Fuzzy Subsets with Analysis of Integer Sequences, Mathematics (2022) Vol. 10, No. 7, 1161.
-
[Factorial(n-4)*StirlingSecond(n+2,n-3): n in [4..35]]; // G. C. Greubel, Nov 22 2022
-
a:= n-> Stirling2(2+n,n-3)*(n-4)!:
seq(a(n), n=4..21); # Alois P. Heinz, Apr 27 2022
-
Table[(n-4)!*StirlingS2[n+2, n-3], {n,4,35}] (* G. C. Greubel, Nov 22 2022 *)
-
[factorial(n-4)*stirling_number2(n+2,n-3) for n in range(4,36)] # G. C. Greubel, Nov 22 2022
A005464
Number of simplices in barycentric subdivision of n-simplex.
Original entry on oeis.org
1, 127, 6050, 204630, 5921520, 158838240, 4115105280, 105398092800, 2706620716800, 70309810771200, 1858166876966400, 50148628078348800, 1385482985542656000, 39245951652171264000, 1140942623868343296000, 34060437199245929472000, 1044402668566817624064000, 32895725269182358302720000
Offset: 5
- R. Austin, R. K. Guy, and R. Nowakowski, unpublished notes, circa 1987.
- R. K. Guy, personal communication.
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
- G. C. Greubel, Table of n, a(n) for n = 5..440
- R. Austin, R. K. Guy, and R. Nowakowski, Unpublished notes, 1987
- Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
- Rajesh Kumar Mohapatra and Tzung-Pei Hong, On the Number of Finite Fuzzy Subsets with Analysis of Integer Sequences, Mathematics (2022) Vol. 10, No. 7, 1161.
-
[Factorial(n-5)*StirlingSecond(n+2,n-4): n in [5..35]]; // G. C. Greubel, Nov 22 2022
-
seq((d+2)!*(63*d^5-945*d^4+5355*d^3-13951*d^2+15806*d-5304)/2903040,d=5..30) ; # R. J. Mathar, Mar 19 2018
-
Table[(n-5)!*StirlingS2[n+2, n-4], {n,5,35}] (* G. C. Greubel, Nov 22 2022 *)
-
[factorial(n-5)*stirling_number2(n+2,n-4) for n in range(5,36)] # G. C. Greubel, Nov 22 2022
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