A111146
Triangle T(n,k), read by rows, given by [0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, ...] DELTA [1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, ...] where DELTA is the operator defined in A084938.
Original entry on oeis.org
1, 0, 1, 0, 0, 2, 0, 0, 1, 4, 0, 0, 2, 5, 8, 0, 0, 6, 15, 17, 16, 0, 0, 24, 62, 68, 49, 32, 0, 0, 120, 322, 359, 243, 129, 64, 0, 0, 720, 2004, 2308, 1553, 756, 321, 128, 0, 0, 5040, 14508, 17332, 11903, 5622, 2151, 769, 256, 0, 0, 40320, 119664
Offset: 0
Triangle begins:
.1;
.0, 1;
.0, 0, 2;
.0, 0, 1, 4;
.0, 0, 2, 5, 8;
.0, 0, 6, 15, 17, 16;
.0, 0, 24, 62, 68, 49, 32;
.0, 0, 120, 322, 359, 243, 129, 64;
.0, 0, 720, 2004, 2308, 1553, 756, 321, 128;
.0, 0, 5040, 14508, 17332, 11903, 5622, 2151, 769, 256;
.0, 0, 40320, 119664, 148232, 105048, 49840, 18066, 5756, 1793, 512;
....................................................................
At y=2: Sum_{k=0..n} 2^k*T(n,k) = A113327(n) where (1 + 2*x + 8*x^2 + 36*x^3 +...+ A113327(n)*x^n +..) = 1/(1 - 2/1!*x*(1! + 2!*x + 3!*x^2 + 4!*x^3 +..) ).
At y=3: Sum_{k=0..n} 3^k*T(n,k) = A113328(n) where (1 + 3*x + 18*x^2 + 117*x^3 +...+ A113328(n)*x^n +..) = 1/(1 - 3/2!*x*(2! + 3!*x + 4!*x^2 + 5!*x^3 +..) ).
At y=4: Sum_{k=0..n} 4^k*T(n,k) = A113329(n) where (1 + 4*x + 32*x^2 + 272*x^3 +...+ A113329(n)*x^n +..) = 1/(1 - 4/3!*x*(3! + 4!*x + 5!*x^2 + 6!*x^3 +..) ).
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T[n_, k_] := Module[{x = X + X*O[X]^n, y = Y + Y*O[Y]^k}, A = 1/(1 - x*y*Sum[x^j*Product[y + i, {i, 0, j - 1}], {j, 0, n}]); Coefficient[ Coefficient[A, X, n], Y, k]];
Table[T[n, k], {n, 0, 10}, {k, 0, n}] // Flatten (* Jean-François Alcover, May 26 2019, from PARI *)
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{T(n,k)=local(x=X+X*O(X^n),y=Y+Y*O(Y^k)); A=1/(1-x*y*sum(j=0,n,x^j*prod(i=0,j-1,y+i))); return(polcoeff(polcoeff(A,n,X),k,Y))} (Hanna)
A114799
Septuple factorial, 7-factorial, n!7, n!!!!!!!, a(n) = n*a(n-7) if n > 1, else 1.
Original entry on oeis.org
1, 1, 2, 3, 4, 5, 6, 7, 8, 18, 30, 44, 60, 78, 98, 120, 288, 510, 792, 1140, 1560, 2058, 2640, 6624, 12240, 19800, 29640, 42120, 57624, 76560, 198720, 379440, 633600, 978120, 1432080, 2016840, 2756160, 7352640, 14418720, 24710400, 39124800
Offset: 0
a(40) = 40 * a(40-7) = 40 * a(33) = 40 * (33*a(26)) = 40 * 33 * (26*a(19)) = 40 * 33 * 26 * (19*a(12)) = 40 * 33 * 26 * 19 * (12*a(5)) = 40 * 33 * 26 * 19 * 12 5 = 39124800.
Cf. k-fold factorials:
A000142,
A001147 (and
A000165,
A006882),
A007559 (and
A032031,
A008544,
A007661),
A007696 (and
A001813,
A008545,
A047053,
A007662),
A008548 (and
A052562,
A047055,
A085157),
A085158 (and
A008542,
A047058,
A047657),
A045755.
-
a:= function(n)
if n<1 then return 1;
else return n*a(n-7);
fi;
end;
List([0..40], n-> a(n) ); # G. C. Greubel, Aug 20 2019
-
b:= func< n | (n lt 8) select n else n*Self(n-7) >;
[1] cat [b(n): n in [1..40]]; // G. C. Greubel, Aug 20 2019
-
A114799 := proc(n)
option remember;
if n < 1 then
1;
else
n*procname(n-7) ;
end if;
end proc:
seq(A114799(n),n=0..40) ; # R. J. Mathar, Jun 23 2014
A114799 := n -> product(n-7*k,k=0..(n-1)/7); # M. F. Hasler, Feb 23 2018
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a[n_]:= If[n<1, 1, n*a[n-7]]; Table[a[n], {n,0,40}] (* G. C. Greubel, Aug 20 2019 *)
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A114799(n,k=7)=prod(j=0,(n-1)\k,n-j*k) \\ M. F. Hasler, Feb 23 2018
-
def a(n):
if (n<1): return 1
else: return n*a(n-7)
[a(n) for n in (0..40)] # G. C. Greubel, Aug 20 2019
A034300
a(n) = n-th quintic factorial number divided by 3.
Original entry on oeis.org
1, 8, 104, 1872, 43056, 1205568, 39783744, 1511782272, 65006637696, 3120318609408, 165376886298624, 9591859405320192, 604287142535172096, 41091525692391702528, 2999681375544594284544, 233975147292478354194432, 19419937225275703398137856, 1708954475824261899036131328
Offset: 1
-
List([1..25], n-> Product([1..n], k-> 5*k-2)/3 ); # G. C. Greubel, Aug 23 2019
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[(&*[5*k-2: k in [1..n]])/3: n in [1..25]]; // G. C. Greubel, Aug 23 2019
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a:= n-> mul(5*k-2, k=1..n)/3; seq(a(n), n=1..25); # G. C. Greubel, Aug 23 2019
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Table[Product[5j-2,{j,n}],{n,20}]*1/3 (* Harvey P. Dale, Jul 25 2011 *)
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a(n) = prod(k=1,n, 5*k-2)/3;
vector(25, n, a(n)) \\ G. C. Greubel, Aug 23 2019
-
[5^n*rising_factorial(3/5, n)/3 for n in (1..25)] # G. C. Greubel, Aug 23 2019
A034323
a(n) = n-th quintic factorial number divided by 2.
Original entry on oeis.org
1, 7, 84, 1428, 31416, 848232, 27143424, 1004306688, 42180880896, 1982501402112, 103090072909824, 5876134155859968, 364320317663318016, 24409461283442307072, 1757481212407846109184, 135326053355404150407168, 11096736375143140333387776, 965416064637453209004736512
Offset: 1
-
a:=[1];; for n in [2..20] do a[n]:=(5*n-3)*a[n-1]; od; a; # G. C. Greubel, Feb 10 2019
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[(&*[5*j-3: j in [1..n]])/2: n in [1..20]]; // G. C. Greubel, Feb 10 2019
-
f:= gfun:-rectoproc({a(n)=(5*n-3)*a(n-1),a(1)=1},a(n),remember):
map(f, [$1..40]); # Robert Israel, Feb 10 2019
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Table[Product[5j-3,{j,n}]/2,{n,20}] (* Harvey P. Dale, Nov 25 2013 *)
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vector(20, n, prod(j=1, n, 5*j-3)/2) \\ G. C. Greubel, Feb 10 2019
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[product(5*j-3 for j in (1..n))/2 for n in (1..20)] # G. C. Greubel, Feb 10 2019
A034325
a(n) is the n-th quintic factorial number divided by 5.
Original entry on oeis.org
1, 10, 150, 3000, 75000, 2250000, 78750000, 3150000000, 141750000000, 7087500000000, 389812500000000, 23388750000000000, 1520268750000000000, 106418812500000000000, 7981410937500000000000, 638512875000000000000000
Offset: 1
-
List([1..20], n-> 5^(n-1)*Factorial(n) ); # G. C. Greubel, Aug 23 2019
-
[5^(n-1)*Factorial(n): n in [1..20]]; // G. C. Greubel, Aug 23 2019
-
seq(5^(n-1)*n!, n=1..20); # G. C. Greubel, Aug 23 2019
-
Array[5^(# - 1) #! &, 16] (* Michael De Vlieger, May 30 2019 *)
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vector(20, n, 5^(n-1)*n!) \\ G. C. Greubel, Aug 23 2019
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[5^(n-1)*factorial(n) for n in (1..20)] # G. C. Greubel, Aug 23 2019
A157396
A partition product of Stirling_2 type [parameter k = -6] with biggest-part statistic (triangle read by rows).
Original entry on oeis.org
1, 1, 6, 1, 18, 66, 1, 144, 264, 1056, 1, 600, 4620, 5280, 22176, 1, 4950, 68640, 110880, 133056, 576576, 1, 26586, 639870, 3141600, 3259872, 4036032, 17873856, 1, 234528, 10759056, 69263040, 105557760, 113008896, 142990848
Offset: 1
A346984
Expansion of e.g.f. 1 / (6 - 5 * exp(x))^(1/5).
Original entry on oeis.org
1, 1, 7, 85, 1495, 34477, 983983, 33476437, 1322441575, 59492222077, 3002578396255, 168005805229285, 10321907081030167, 690761732852321677, 50015387402165694607, 3895721046926471861365, 324805103526730206129607, 28861947117644330678207389, 2722944810091827410698112959
Offset: 0
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g:= proc(n) option remember; `if`(n<2, 1, (5*n-4)*g(n-1)) end:
b:= proc(n, m) option remember;
`if`(n=0, g(m), m*b(n-1, m)+b(n-1, m+1))
end:
a:= n-> b(n, 0):
seq(a(n), n=0..18); # Alois P. Heinz, Aug 09 2021
-
nmax = 18; CoefficientList[Series[1/(6 - 5 Exp[x])^(1/5), {x, 0, nmax}], x] Range[0, nmax]!
Table[Sum[StirlingS2[n, k] 5^k Pochhammer[1/5, k], {k, 0, n}], {n, 0, 18}]
A256268
Table of k-fold factorials, read by antidiagonals.
Original entry on oeis.org
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 6, 3, 1, 1, 1, 24, 15, 4, 1, 1, 1, 120, 105, 28, 5, 1, 1, 1, 720, 945, 280, 45, 6, 1, 1, 1, 5040, 10395, 3640, 585, 66, 7, 1, 1, 1, 40320, 135135, 58240, 9945, 1056, 91, 8, 1, 1, 1, 362880, 2027025, 1106560, 208845, 22176, 1729, 120, 9, 1, 1
Offset: 0
1 1 1 1 1 1 1... A000012
1 1 2 6 24 120 720... A000142
1 1 3 15 105 945 10395... A001147
1 1 4 28 280 3640 58240... A007559
1 1 5 45 585 9945 208845... A007696
1 1 6 66 1056 22176 576576... A008548
1 1 7 91 1729 43225 1339975... A008542
1 1 8 120 2640 76560 2756160... A045754
1 1 9 153 3825 126225 5175225... A045755
1 1 10 190 5320 196840 9054640... A045756
1 1 11 231 7161 293601 14977651... A144773
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Flat(List([0..12], n-> List([0..n], k-> Product([0..n-k-1], j-> j*k+1) ))); # G. C. Greubel, Mar 04 2020
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function T(n,k)
if k eq 0 or n eq 0 then return 1;
else return (&*[j*k+1: j in [0..n-1]]);
end if; return T; end function;
[T(n-k,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Mar 04 2020
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seq(seq( mul(j*k+1, j=0..n-k-1), k=0..n), n=0..12); # G. C. Greubel, Mar 04 2020
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T[n_, k_]= Product[j*k+1, {j,0,n-1}]; Table[T[n-k,k], {n,0,12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 04 2020 *)
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T(n,k) = prod(j=0, n-1, j*k+1);
for(n=0,12, for(k=0, n, print1(T(n-k, k), ", "))) \\ G. C. Greubel, Mar 04 2020
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[[ product(j*k+1 for j in (0..n-k-1)) for k in (0..n)] for n in (0..12)] # G. C. Greubel, Mar 04 2020
A257623
Triangle read by rows: T(n,k) = t(n-k, k), where t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1) and f(n) = 5*n + 3.
Original entry on oeis.org
1, 3, 3, 9, 48, 9, 27, 501, 501, 27, 81, 4494, 13026, 4494, 81, 243, 37815, 250230, 250230, 37815, 243, 729, 309324, 4122735, 9008280, 4122735, 309324, 729, 2187, 2498649, 62256627, 256971945, 256971945, 62256627, 2498649, 2187
Offset: 0
Array, t(n,k), begins as:
1, 3, 9, 27, 81, ... A000244;
3, 48, 501, 4494, 37815, ...;
9, 501, 13026, 250230, 4122735, ...;
27, 4494, 250230, 9008280, 256971945, ...;
81, 37815, 4122735, 256971945, 11820709470, ...;
243, 309324, 62256627, 6368680566, 450199373658, ...;
729, 2498649, 891791568, 144065371932, 15108742867890, ...;
Triangle, T(n,k), begins as:
1;
3, 3;
9, 48, 9;
27, 501, 501, 27;
81, 4494, 13026, 4494, 81;
243, 37815, 250230, 250230, 37815, 243;
729, 309324, 4122735, 9008280, 4122735, 309324, 729;
2187, 2498649, 62256627, 256971945, 256971945, 62256627, 2498649, 2187;
Similar sequences listed in
A256890.
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t[n_, k_, p_, q_]:= t[n, k, p, q]= If[n<0 || k<0, 0, If[n==0 && k==0, 1, (p*k+ q)*t[n-1,k,p,q] + (p*n+q)*t[n,k-1,p,q]]];
T[n_, k_, p_, q_]= t[n-k,k,p,q];
Table[T[n,k,5,3], {n,0,12}, {k,0,n}]//Flatten (* G. C. Greubel, Feb 27 2022 *)
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@CachedFunction
def t(n,k,p,q):
if (n<0 or k<0): return 0
elif (n==0 and k==0): return 1
else: return (p*k+q)*t(n-1,k,p,q) + (p*n+q)*t(n,k-1,p,q)
def A257623(n,k): return t(n-k,k,5,3)
flatten([[A257623(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Feb 27 2022
A051150
Generalized Stirling number triangle of first kind.
Original entry on oeis.org
1, -5, 1, 50, -15, 1, -750, 275, -30, 1, 15000, -6250, 875, -50, 1, -375000, 171250, -28125, 2125, -75, 1, 11250000, -5512500, 1015000, -91875, 4375, -105, 1, -393750000, 204187500, -41037500, 4230625
Offset: 1
Triangle a(n,m) (with rows n >= 1 and columns m = 1..n) begins:
1;
-5, 1;
50, -15, 1;
-750, 275, -30, 1;
15000, -6250, 875, -50, 1;
-375000, 171250, -28125, 2125, -75, 1;
...
3rd row o.g.f.: E(3,x) = 50*x - 15*x^2 + x^3.
- Wolfdieter Lang, First 10 rows.
- D. S. Mitrinovic, Sur une classe de nombres reliés aux nombres de Stirling, Comptes rendus de l'Académie des sciences de Paris, t. 252 (1961), 2354-2356. [The numbers R_n^m(a,b) are first introduced.]
- D. S. Mitrinovic and R. S. Mitrinovic, Tableaux d'une classe de nombres reliés aux nombres de Stirling, Univ. Beograd. Publ. Elektrotehn. Fak. Ser. Mat. Fiz., No. 77 (1962), 1-77. [Special cases of the numbers R_n^m(a,b) are tabulated.]
First (m=1) column sequence:
A052562(n-1).
Row sums (signed triangle):
A008546(n-1)*(-1)^(n-1).
Row sums (unsigned triangle):
A008548(n).
Comments