A051717
1, followed by denominators of first differences of Bernoulli numbers (B(i)-B(i-1)).
Original entry on oeis.org
1, 2, 3, 6, 30, 30, 42, 42, 30, 30, 66, 66, 2730, 2730, 6, 6, 510, 510, 798, 798, 330, 330, 138, 138, 2730, 2730, 6, 6, 870, 870, 14322, 14322, 510, 510, 6, 6, 1919190, 1919190, 6, 6, 13530, 13530, 1806, 1806, 690, 690, 282, 282, 46410, 46410, 66, 66, 1590, 1590
Offset: 0
Bernoulli numbers: 1, -1/2, 1/6, 0, -1/30, 0, 1/42, 0, -1/30, 0, 5/66, ...
First differences: -3/2, 2/3, -1/6, -1/30, 1/30, 1/42, -1/42, -1/30, ...
Numerators: -3, 2, -1, -1, 1, 1, -1, -1, 1, 5, -5, -691, 691, 7, ...
Denominators: 2, 3, 6, 30, 30, 42, 42, 30, 30, 66, 66, 2730, ...
Sequence of C(n)'s begins: 1, -1/2, -1/3, -1/6, -1/30, 1/30, 1/42, -1/42, -1/30, 1/30, 5/66, -5/66, -691/2730, 691/2730, 7/6, -7/6, ...
-
f:= func< n | Bernoulli(n) + Bernoulli(n-1) >;
function A051717(n)
if n eq 0 then return 1;
elif (n mod 2) eq 0 then return Denominator(f(n));
else return Denominator(-f(n));
end if;
end function;
[A051717(n): n in [0..50]]; // G. C. Greubel, Apr 22 2023
-
C:=proc(n) if n=0 then RETURN(1); fi; if n mod 2 = 0 then RETURN(bernoulli(n)+bernoulli(n-1)); else RETURN(-bernoulli(n)-bernoulli(n-1)); fi; end;
-
c[0]= 1; c[n_?EvenQ]:= BernoulliB[n] + BernoulliB[n-1]; c[n_?OddQ]:= -BernoulliB[n] - BernoulliB[n-1]; Table[Denominator[c[n]], {n,0,53}] (* Jean-François Alcover, Dec 19 2011 *)
Join[{1},Denominator[Total/@Partition[BernoulliB[Range[0,60]],2,1]]] (* Harvey P. Dale, Mar 09 2013 *)
Join[{1},Denominator[Differences[BernoulliB[Range[0,60]]]]] (* Harvey P. Dale, Jun 28 2021 *)
-
a(n)=if(n<3,n+1,denominator(bernfrac(n)-bernfrac(n-1))) \\ Charles R Greathouse IV, May 18 2015
-
def f(n): return bernoulli(n)+bernoulli(n-1)
def A051717(n):
if (n==0): return 1
elif (n%2==0): return denominator(f(n))
else: return denominator(-f(n))
[A051717(n) for n in range(51)] # G. C. Greubel, Apr 22 2023
A051716
Numerators of Bernoulli twin numbers C(n).
Original entry on oeis.org
1, -1, -1, -1, -1, 1, 1, -1, -1, 1, 5, -5, -691, 691, 7, -7, -3617, 3617, 43867, -43867, -174611, 174611, 854513, -854513, -236364091, 236364091, 8553103, -8553103, -23749461029, 23749461029, 8615841276005, -8615841276005, -7709321041217, 7709321041217, 2577687858367
Offset: 0
The C(n) sequence is 1, -1/2, -1/3, -1/6, -1/30, 1/30, 1/42, -1/42, -1/30, 1/30, 5/66, -5/66, -691/2730, 691/2730, 7/6, -7/6, ...
-
f:= func< n | Bernoulli(n) + Bernoulli(n-1) >;
function A051716(n)
if n eq 0 then return 1;
elif (n mod 2) eq 0 then return Numerator(f(n));
else return Numerator(-f(n));
end if;
end function;
[A051716(n): n in [0..50]]; // G. C. Greubel, Apr 22 2023
-
C:=proc(n) if n=0 then RETURN(1); fi; if n mod 2 = 0 then RETURN(bernoulli(n)+bernoulli(n-1)); else RETURN(-bernoulli(n)-bernoulli(n-1)); fi; end;
-
c[0]= 1; c[n_?EvenQ]:= BernoulliB[n] + BernoulliB[n-1]; c[n_?OddQ]:= -BernoulliB[n] - BernoulliB[n-1]; Table[Numerator[c[n]], {n,0,34}] (* Jean-François Alcover, Dec 19 2011 *)
-
a(n) = if (n==0, 1, nu = numerator(bernfrac(n)+bernfrac(n-1)); if (n%2, -nu, nu)); \\ Michel Marcus, Jan 29 2017
-
def f(n): return bernoulli(n)+bernoulli(n-1)
def A051716(n):
if (n==0): return 1
elif (n%2==0): return numerator(f(n))
else: return numerator(-f(n))
[A051716(n) for n in range(51)] # G. C. Greubel, Apr 22 2023
A161739
The RSEG2 triangle.
Original entry on oeis.org
1, 0, 1, 0, 1, 1, 0, 1, 4, 1, 0, 0, 13, 10, 1, 0, -4, 30, 73, 20, 1, 0, 0, -14, 425, 273, 35, 1, 0, 120, -504, 1561, 3008, 798, 56, 1, 0, 0, 736, -2856, 25809, 14572, 1974, 84, 1, 0, -12096, 44640, -73520, 125580, 218769, 55060, 4326, 120, 1
Offset: 0
The first few expressions for the ZG1[2*m-1,p+1] coefficients are:
ZG1[2*m-1, 1] = (zeta(2*m-1))/(1/2)
ZG1[2*m-1, 2] = (zeta(2*m-3) - zeta(2*m-1))/1
ZG1[2*m-1, 3] = (zeta(2*m-5) - 5*zeta(2*m-3) + 4*zeta(2*m-1))/6
ZG1[2*m-1, 4] = (zeta(2*m-7) - 14*zeta(2*m-5) + 49*zeta(2*m-3) - 36*zeta(2*m-1))/72
The first few rs(2*m,p) are (m >= p+2)
rs(2*m, p=0) = ZG1[2*m-1,1]
rs(2*m, p=1) = ZG1[2*m-1,1] + ZG1[2*m-1,2]
rs(2*m, p=2) = ZG1[2*m-1,1] + 3*ZG1[2*m-1,2] + 2*ZG1[2*m-1,3]
rs(2*m, p=3) = ZG1[2*m-1,1] + 7*ZG1[2*m-1,2] + 12*ZG1[2*m-1,3] + 6*ZG1[2*m-1,4]
The first few rs(2*m,p) are (m >= p+2)
rs(2*m, p=-1) = zeta(2*m+1)/(1/2)
rs(2*m, p=0) = zeta(2*m-1)/(1/2)
rs(2*m, p=1) = (zeta(2*m-1) + zeta(2*m-3))/1
rs(2*m, p=2) = (zeta(2*m-1) + 4*zeta(2*m-3) + zeta(2*m-5))/3
rs(2*m, p=3) = (0*zeta(2*m-1) + 13*zeta(2*m-3) + 10*zeta(2*m-5) + zeta(2*m-7))/12
The first few rows of the RSEG2 triangle are:
[1]
[0, 1]
[0, 1, 1]
[0, 1, 4, 1]
[0, 0, 13, 10, 1]
[0, -4, 30, 73, 20, 1]
- M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972, Chapter 23, pp. 811-812.
- J. W. Meijer and N.H.G. Baken, The Exponential Integral Distribution, Statistics and Probability Letters, Volume 5, No.3, April 1987. pp 209-211.
A008955 is a central factorial number triangle.
-
nmax:=10; for n from 0 to nmax do A008955(n, 0) := 1 end do: for n from 0 to nmax do A008955(n, n) := (n!)^2 end do: for n from 1 to nmax do for m from 1 to n-1 do A008955(n, m) := A008955(n-1, m-1)*n^2 + A008955(n-1, m) end do: end do: for n from 1 to nmax do A028246(n, 1) := 1 od: for n from 1 to nmax do A028246(n, n) := (n-1)! od: for n from 3 to nmax do for m from 2 to n-1 do A028246(n, m) := m*A028246(n-1, m) + (m-1)*A028246(n-1, m-1) od: od: for i from 0 to nmax-2 do s(i) := ((i+1)!/2)*sum(A028246(i+1, k1+1)*(sum((-1)^(j)*A008955(k1, j)*2*x^(2*nmax-(2*k1+1-2*j)), j=0..k1)/ (k1!*(k1+1)!)), k1=0..i) od: a(0,0) := 1: for n from 1 to nmax-1 do for m from 0 to n do a(n,m) := coeff(s(n-1), x, 2*nmax-1-2*m+2) od: od: seq(seq(a(n, m), m=0..n), n=0..nmax-1); for n from 0 to nmax-1 do seq(a(n, m), m=0..n) od;
m:=7: row := 2*m; rs(2*m, -2) := 2*eta(2*m+2); for p from -1 to m-2 do q(p+1) := (p+1)!/2 od: for p from -1 to m-2 do rs(2*m, p) := sum(a(p+1, k)*zeta(2*m+1-2*k), k=0..p+1)/q(p+1) od;
A094310
Triangle read by rows: T(n,k), the k-th term of the n-th row, is the product of all numbers from 1 to n except k: T(n,k) = n!/k.
Original entry on oeis.org
1, 2, 1, 6, 3, 2, 24, 12, 8, 6, 120, 60, 40, 30, 24, 720, 360, 240, 180, 144, 120, 5040, 2520, 1680, 1260, 1008, 840, 720, 40320, 20160, 13440, 10080, 8064, 6720, 5760, 5040, 362880, 181440, 120960, 90720, 72576, 60480, 51840, 45360, 40320, 3628800, 1814400, 1209600, 907200, 725760, 604800, 518400, 453600, 403200, 362880
Offset: 1
Triangle begins as:
1;
2, 1;
6, 3, 2;
24, 12, 8, 6;
120, 60, 40, 30, 24;
720, 360, 240, 180, 144, 120;
5040, 2520, 1680, 1260, 1008, 840, 720;
40320, 20160, 13440, 10080, 8064, 6720, 5760, 5040;
...
T(4,2) counts the 12 permutations of [4] with elements 1 and 2 in the same cycle, namely, (1 2)(3 4), (1 2)(3)(4), (1 2 3)(4), (1 3 2)(4), (1 2 4)(3), (1 4 2)(3), (1 2 3 4), (1 2 4 3), (1 3 2 4), (1 3 4 2), (1 4 2 3), and (1 4 3 2). - _Dennis P. Walsh_, May 24 2020
-
seq(seq(n!/k, k=1..n), n=1..10);
-
Table[n!/k, {n,10}, {k,n}]//Flatten
Table[n!/Range[n], {n,10}]//Flatten (* Harvey P. Dale, Mar 12 2016 *)
A161742
Third left hand column of the RSEG2 triangle A161739.
Original entry on oeis.org
1, 4, 13, 30, -14, -504, 736, 44640, -104544, -10644480, 33246720, 5425056000, -20843695872, -5185511654400, 23457840537600, 8506857655296000, -44092609863966720, -22430879475779174400, 130748316971139072000
Offset: 2
Equals third left hand column of
A161739 (RSEG2 triangle).
A008955 is a central factorial number triangle.
-
nmax:=21; for n from 0 to nmax do A008955(n,0):=1 end do: for n from 0 to nmax do A008955(n,n):=(n!)^2 end do: for n from 1 to nmax do for m from 1 to n-1 do A008955(n,m):= A008955(n-1,m-1)*n^2+A008955(n-1,m) end do: end do: for n from 1 to nmax do A028246(n,1):=1 od: for n from 1 to nmax do A028246(n,n):=(n-1)! od: for n from 3 to nmax do for m from 2 to n-1 do A028246(n,m):=m*A028246(n-1,m)+(m-1)*A028246(n-1,m-1) od: od: for n from 2 to nmax do a(n):=sum(((-1)^k/((k+1)!*(k+2)!)) *(n!)*A028246(n,k+2)* A008955(k+1,k),k=0..n-2) od: seq(a(n),n=2..nmax);
A161743
Fourth left hand column of the RSEG2 triangle A161739.
Original entry on oeis.org
1, 10, 73, 425, 1561, -2856, -73520, 380160, 15376416, -117209664, -7506967104, 72162155520, 7045087741056, -80246202992640, -11448278791372800, 149576169325363200, 30017051616972275712, -440857664887810867200
Offset: 3
Equals fourth left hand column of
A161739 (RSEG2 triangle).
A008955 is a central factorial number triangle.
-
nmax:=21; for n from 0 to nmax do A008955(n,0):=1 end do: for n from 0 to nmax do A008955(n,n):=(n!)^2 end do: for n from 1 to nmax do for m from 1 to n-1 do A008955(n,m):= A008955(n-1,m-1)*n^2+A008955(n-1,m) end do: end do: for n from 1 to nmax do A028246(n,1):=1 od: for n from 1 to nmax do A028246(n,n):=(n-1)! od: for n from 3 to nmax do for m from 2 to n-1 do A028246(n,m):=m*A028246(n-1,m)+(m-1)*A028246(n-1,m-1) od: od: for n from 3 to nmax do a(n) := sum(((-1)^k/((k+2)!*(k+3)!))*(n!)*A028246(n,k+3)* A008955(k+2,k), k=0..n-3) od: seq(a(n),n=3..nmax);
A129724
a(0) = 1; then a(n) = n!*(1 - (-1)^n*Bernoulli(n-1)).
Original entry on oeis.org
1, 2, 3, 7, 24, 116, 720, 5160, 40320, 350784, 3628800, 42940800, 479001600, 4650877440, 87178291200, 2833294464000, 20922789888000, -2166903606067200, 6402373705728000, 6808619561103360000, 2432902008176640000, -26982365129174827008000, 1124000727777607680000
Offset: 0
-
Concatenation([1], List([1..25], n-> Factorial(n)*(1 - (-1)^n*Bernoulli(n-1)) )); # G. C. Greubel, Dec 03 2019
-
[n eq 0 select 1 else Factorial(n)*(1 - (-1)^n*Bernoulli(n-1)): n in [0..25]]; // G. C. Greubel, Dec 03 2019
-
a:= proc(n)
if n=0 and n>=0 then 1
elif n mod 2 = 0 then n!*(1 - bernoulli(n-1))
else n!*(1 + bernoulli(n-1))
fi; end;
seq(a(n), n=0..25); # modified by G. C. Greubel, Dec 03 2019
-
a[0] = 1; a[n_]:= n!*(1-(-1)^n*BernoulliB[n-1]); Table[a[n], {n, 0, 22}] (* Jean-François Alcover, Sep 16 2013 *)
-
a(n) = if(n==0, 1, n!*(1 - (-1)^n*bernfrac(n-1)) ); \\ G. C. Greubel, Dec 03 2019
-
[1]+[factorial(n)*(1 - (-1)^n*bernoulli(n-1)) for n in (1..25)] # G. C. Greubel, Dec 03 2019
A137777
Triangular sequence of coefficients from the expansion of the derivative of the Bernoulli polynomial function: p(x,t) = t*exp(x*t)/(exp(t)-1); q(x,t) = p'(x,t) = dp(x,t)/dt.
Original entry on oeis.org
2, -2, 4, 2, -12, 12, 0, 24, -72, 48, -8, 0, 240, -480, 240, 0, -240, 0, 2400, -3600, 1440, 240, 0, -5040, 0, 25200, -30240, 10080, 0, 13440, 0, -94080, 0, 282240, -282240, 80640, -24192, 0, 483840, 0, -1693440, 0, 3386880, -2903040, 725760, 0, -2177280, 0, 14515200, 0, -30481920, 0, 43545600, -32659200
Offset: 0
{2},
{-2, 4},
{2, -12, 12},
{0,24, -72, 48},
{-8, 0, 240, -480, 240},
{0, -240, 0, 2400, -3600, 1440},
{240, 0, -5040, 0, 25200, -30240, 10080},
{0, 13440, 0, -94080, 0, 282240, -282240, 80640},
{-24192, 0, 483840, 0, -1693440, 0, 3386880, -2903040, 725760},
{0, -2177280, 0, 14515200, 0, -30481920, 0, 43545600, -32659200, 7257600},
{6048000, 0, -119750400, 0, 399168000, 0, -558835200, 0, 598752000, -399168000, 79833600},
{0, 798336000, 0, -5269017600, 0, 10538035200, 0, -10538035200, 0, 8781696000, -5269017600, 958003200}
-
seq(seq(coeff(bernoulli(k,x)*2*(k+1)!,x,i),i=0..k),k=1..10); # Peter Luschny, Apr 23 2009
-
Clear[p, b, a]; p[t_] = D[t^2*Exp[x*t]/(Exp[t]-1),{t,1}];
a = Table[CoefficientList[2*n!^2*SeriesCoefficient
[Series[p[t],{t,0,30}],n],x],{n,0,10}]; Flatten[a]
Table[CoefficientList[2 BernoulliB[k,x] Gamma[2+k],x],{k,0,10}]//Flatten
A363041
Triangle read by rows: T(n,k) = Stirling2(n+1,k)/binomial(k+1,2) if n-k is even, else 0 (1 <= k <= n).
Original entry on oeis.org
1, 0, 1, 1, 0, 1, 0, 5, 0, 1, 1, 0, 15, 0, 1, 0, 21, 0, 35, 0, 1, 1, 0, 161, 0, 70, 0, 1, 0, 85, 0, 777, 0, 126, 0, 1, 1, 0, 1555, 0, 2835, 0, 210, 0, 1, 0, 341, 0, 14575, 0, 8547, 0, 330, 0, 1, 1, 0, 14421, 0, 91960, 0, 22407, 0, 495, 0, 1
Offset: 1
Triangle begins
k = 1 2 3 4 5 6 7 8 9 10
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
n = 1: 1
2: 0 1
3: 1 0 1
4: 0 5 0 1
5: 1 0 15 0 1
6: 0 21 0 35 0 1
7: 1 0 161 0 70 0 1
8: 0 85 0 777 0 126 0 1
9: 1 0 1555 0 2835 0 210 0 1
10: 0 341 0 14575 0 8547 0 330 0 1
...
Matrix product (|A008275|)^-1 * A164652 * A008277 begins
/ 1 \ /1 \ /1 \ /1 \
|-1 1 | |0 1 | |1 1 | |0 1 |
| 1 -3 1 | |1 0 1 | |1 3 1 | = |0 0 1 |
|-1 7 -6 1 | |0 5 0 1 | |1 7 6 1 | |0 1 0 1 |
| 1 -15 25 -10 1| |8 0 15 0 1| |1 15 25 10 1| |0 0 5 0 1 |
| ... | |... | |... | |0 1 0 15 0 1|
| | | | | | |... |
-
A362041:= (n, k)-> `if`(n-k mod 2 = 0, Stirling2(n+1,k)/binomial(k+1,2), 0):
for n from 1 to 10 do seq(A362041(n,k), k = 1..n) od;
-
T(n,k) = if ((n-k) % 2, 0, stirling(n+1, k, 2)/binomial(k+1, 2)); \\ Michel Marcus, May 23 2023
Showing 1-9 of 9 results.
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