A060818 -id:A060818 - cp's OEIS frontend

A082907 A modified Pascal's triangle, read by rows, and modified as follows: binomial(n,j) is replaced by gcd(2^n, binomial(n,j)), i.e., the largest power of 2 dividing binomial(n,j).

1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 4, 2, 4, 1, 1, 1, 2, 2, 1, 1, 1, 2, 1, 4, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 8, 4, 8, 2, 8, 4, 8, 1, 1, 1, 4, 4, 2, 2, 4, 4, 1, 1, 1, 2, 1, 8, 2, 4, 2, 8, 1, 2, 1, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 1, 4, 2, 4, 1, 8, 4, 8, 1, 4, 2, 4, 1, 1, 1, 2, 2, 1, 1, 4, 4, 1, 1, 2, 2, 1, 1

Offset: 0

Labos Elemer, Apr 23 2003

If N is a power of 2, then the first N rows are invariant under all 6 symmetries of an equilateral triangle. - Paul Boddington, Dec 17 2003

			Triangle read by rows:
            1,
           1,1,
          1,2,1,
         1,1,1,1,
        1,4,2,4,1,
       1,1,2,2,1,1,
      1,2,1,4,1,2,1,
     1,1,1,1,1,1,1,1,
    1,8,4,8,2,8,4,8,1,
   1,1,4,4,2,2,4,4,1,1,
  ...
For n = -1 + 2^k, such rows consist of all 1's since all binomial coefficients C(n,j) are odd.

G. C. Greubel, Table of n, a(n) for the first 50 rows, flattened
Tyler Ball, Tom Edgar, and Daniel Juda, Dominance Orders, Generalized Binomial Coefficients, and Kummer's Theorem, Mathematics Magazine, Vol. 87, No. 2, April 2014, pp. 135-143.
E. Burlachenko, Fractal generalized Pascal matrices, arXiv:1612.00970 [math.NT], 2016. See p. 5.
Tom Edgar and Michael Z. Spivey, Multiplicative functions, generalized binomial coefficients, and generalized Catalan numbers, Journal of Integer Sequences, Vol. 19 (2016), Article 16.1.6.

Cf. A000005, A000079, A001316, A007318, A060818.

Flatten[Table[Table[GCD[2^n, Binomial[n, j]], {j, 0, n}], {n, 0, 25}], 1]
f[n_] := Denominator[CatalanNumber[n - 1]/2^(n - 1)]; T[n_, k_] := f[n]/(f[k]*f[n - k]); Table[T[n, k], {n, 0, 7}, {k, 0, n}]//Flatten (* G. C. Greubel, Dec 24 2016 *)

From Paul Boddington, Dec 17 2003: (Start)
T(n, j) = c(n)/(c(j)*c(n-j)) where c(n)=A060818(n).
T(n, j) = (b(j)*b(n-j))/b(n) where b(n)=A001316(n) (Gould's sequence). (End)

Edited by Jon E. Schoenfield, Dec 24 2016

A220002 Numerators of the coefficients of an asymptotic expansion in even powers of the Catalan numbers.

Original entry on oeis.org

1, 5, 21, 715, -162877, 19840275, -7176079695, 1829885835675, -5009184735027165, 2216222559226679575, -2463196751104762933637, 1679951011110471133453965, -5519118103058048675551057049, 5373485053345792589762994345215, -12239617587594386225052760043303511

Offset: 0

Peter Luschny, Dec 27 2012

sign

Let N = 4*n+3 and A = sum_{k>=0} a(k)/(A123854(k)*N^(2*k)) then
C(n) ~ 8*4^n*A/(N*sqrt(N*Pi)), C(n) = (4^n/sqrt(Pi))*(Gamma(n+1/2)/ Gamma(n+2)) the Catalan numbers A000108.
The asymptotic expansion of the Catalan numbers considered here is based on the Taylor expansion of square root of the sine cardinal. This asymptotic series involves only even powers of N, making it more efficient than the asymptotic series based on Stirling's approximation to the central binomial which involves all powers (see for example: D. E. Knuth, 7.2.1.6 formula (16)). The series is discussed by Kessler and Schiff but is included as a special case in the asymptotic expansion given by J. L. Fields for quotients Gamma(x+a)/Gamma(x+b) and discussed by Y. L. Luke (p. 34-35), apparently overlooked by Kessler and Schiff.

			With N = 4*n+3 the first few terms of A are A = 1 + 5/(4*N^2) + 21/(32*N^4) + 715/(128*N^6) - 162877/(2048*N^8) + 19840275/(8192*N^10). With this A C(n) = round(8*4^n*A/(N*sqrt(N*Pi))) for n = 0..39 (if computed with sufficient numerical precision).

Donald E. Knuth, The Art of Computer Programming, Volume 4, Fascicle 4: Generating All Trees—History of Combinatorial Generation, 2006.
Y. L. Luke, The Special Functions and their Approximations, Vol. 1. Academic Press, 1969.

Peter Luschny, Table of n, a(n) for n = 0..99
J. L. Fields, A note on the asymptotic expansion of a ratio of gamma functions, Proc. Edinburgh Math. Soc. 15 (1) (1966), 43-45.
D. Kessler and J. Schiff, The asymptotics of factorials, binomial coefficients and Catalan numbers. April 2006.

The logarithmic version is A220422. Appears in A193365 and A220466.

Cf. A220412.

A220002 := proc(n) local s; s := n -> `if`(n > 0, s(iquo(n,2))+n, 0);
(-1)^n*mul(4*i+2, i = 1..2*n)*2^s(iquo(n,2))*coeff(taylor(sqrt(sin(x)/x), x,2*n+2), x, 2*n) end: seq(A220002(n), n = 0..14);
# Second program illustrating J. L. Fields expansion of gamma quotients.
A220002 := proc(n) local recF, binSum, swing;
binSum := n -> add(i,i=convert(n,base,2));
swing := n -> n!/iquo(n, 2)!^2;
recF := proc(n, x) option remember; `if`(n=0, 1, -2*x*add(binomial(n-1,2*k+1)*bernoulli(2*k+2)/(2*k+2)*recF(n-2*k-2,x),k=0..n/2-1)) end: recF(2*n,-1/4)*2^(3*n-binSum(n))*swing(4*n+1) end:

max = 14; CoefficientList[ Series[ Sqrt[ Sinc[x]], {x, 0, 2*max+1}], x^2][[1 ;; max+1]]*Table[ (-1)^n*Product[ (2*k+1), {k, 1, 2*n}], {n, 0, max}] // Numerator (* Jean-François Alcover, Jun 26 2013 *)

length = 15; T = taylor(sqrt(sin(x)/x),x,0,2*length+2)
def A005187(n): return A005187(n//2) + n if n > 0 else 0
def A220002(n):
    P = mul(4*i+2 for i in (1..2*n)) << A005187(n//2)
    return (-1)^n*P*T.coefficient(x, 2*n)
[A220002(n) for n in range(length)]

# Second program illustrating the connection with the Euler numbers.
def A220002_list(n):
    S = lambda n: sum((4-euler_number(2*k))/(4*k*x^(2*k)) for k in (1..n))
    T = taylor(exp(S(2*n+1)),x,infinity,2*n-1).coefficients()
    return [t[0].numerator() for t in T][::-1]
A220002_list(15)

Let [x^n]T(f(x)) denote the coefficient of x^n in the Taylor expansion of f(x) then r(n) = (-1)^n*prod_{i=1..2n}(2i+1)*[x^(2*n)]T(sqrt(sin(x)/x)) is the rational coefficient of the asymptotic expansion (in N=4*n+3) and a(n) = numerator(r(n)) = r(n)*2^(3*n-bs(n)), where bs(n) is the binary sum of n (A000120).
Also a(n) = numerator([x^(2*n)]T(exp(S))) where S = sum_{k>=1}((4-E(2*k))/ (4*k)*x^(2*k)) and E(n) the Euler numbers A122045.
Also a(n) = sf(4*n+1)*2^(3*n-bs(n))*F_{2*n}(-1/4) where sf(n) is the swinging factorial A056040, bs(n) the binary sum of n and F_{n}(x) J. L. Fields' generalized Bernoulli polynomials A220412.
In terms of sequences this means
r(n) = (-1)^n*A103639(n)*A008991(n)/A008992(n),
a(n) = (-1)^n*A220371(n)*A008991(n)/A008992(n).
Note that a(n) = r(n)*A123854(n) and A123854(n) = 2^A004134(n) = 8^n/2^A000120(n).
Formula from Johannes W. Meijer:
a(n) = d(n+1)*A098597(2*n+1)*(A008991(n)/A008992(n)) with d(1) = 1 and
d(n+1) = -4*(2*n+1)*A161151(n)*d(n),
d(n+1) = (-1)^n*2^(-1)*(2*(n+1))!*A060818(n)*A048896(n).

A163590 Odd part of the swinging factorial A056040.

Original entry on oeis.org

1, 1, 1, 3, 3, 15, 5, 35, 35, 315, 63, 693, 231, 3003, 429, 6435, 6435, 109395, 12155, 230945, 46189, 969969, 88179, 2028117, 676039, 16900975, 1300075, 35102025, 5014575, 145422675, 9694845, 300540195, 300540195, 9917826435, 583401555, 20419054425, 2268783825

Offset: 0

Peter Luschny, Aug 01 2009

nonn

Let n$ denote the swinging factorial. a(n) = n$ / 2^sigma(n) where sigma(n) is the exponent of 2 in the prime-factorization of n$. sigma(n) can be computed as the number of '1's in the base 2 representation of floor(n/2).

If n is even then a(n) is the numerator of the reduced ratio (n-1)!!/n!! = A001147(n-1)/A000165(n), and if n is odd then a(n) is the numerator of the reduced ratio n!!/(n-1)!! = A001147(n)/A000165(n-1). The denominators for each ratio should be compared to A060818. Here all ratios are reduced. - Anthony Hernandez, Feb 05 2020 [See the Mathematica program for a more compact form of the formula. Peter Luschny, Mar 01 2020 ]

			11$ = 2772 = 2^2*3^2*7*11. Therefore a(11) = 3^2*7*11 = 2772/4 = 693.
From _Anthony Hernandez_, Feb 04 2019: (Start)
a(7) = numerator((1*3*5*7)/(2*4*6)) = 35;
a(8) = numerator((1*3*5*7)/(2*4*6*8)) = 35;
a(9) = numerator((1*3*5*7*9)/(2*4*6*8)) = 315;
a(10) = numerator((1*3*5*7*9)/(2*4*6*8*10)) = 63. (End)

G. C. Greubel, Table of n, a(n) for n = 0..1000
Peter Luschny, Die schwingende Fakultät und Orbitalsysteme, August 2011.
Peter Luschny, Swinging Factorial.

Cf. A056040, A060632, A001790, A001803.

swing := proc(n) option remember; if n = 0 then 1 elif irem(n, 2) = 1 then swing(n-1)*n else 4*swing(n-1)/n fi end:
sigma := n -> 2^(add(i,i= convert(iquo(n,2),base,2))):
a := n -> swing(n)/sigma(n);

sf[n_] := With[{f = Floor[n/2]}, Pochhammer[f+1, n-f]/ f!]; a[n_] := With[{s = sf[n]}, s/2^IntegerExponent[s, 2]]; Table[a[n], {n, 0, 31}] (* Jean-François Alcover, Jul 26 2013 *)
r[n_] := (n - Mod[n - 1, 2])!! /(n - 1 + Mod[n - 1, 2])!! ;
Table[r[n], {n, 0, 36}] // Numerator (* Peter Luschny, Mar 01 2020 *)

A163590(n) = {
    my(a = vector(n+1)); a[1] = 1;
    for(n = 1, n,
        a[n+1] = a[n]*n^((-1)^(n+1))*2^valuation(n, 2));
a } \\ Peter Luschny, Sep 29 2019

# uses[A000120]
@CachedFunction
def swing(n):
    if n == 0: return 1
    return swing(n-1)*n if is_odd(n) else 4*swing(n-1)/n
A163590 = lambda n: swing(n)/2^A000120(n//2)
[A163590(n) for n in (0..31)]  # Peter Luschny, Nov 19 2012
# Alternatively:

@cached_function
def A163590(n):
    if n == 0: return 1
    return A163590(n - 1) * n^((-1)^(n + 1)) * 2^valuation(n, 2)
print([A163590(n) for n in (0..31)]) # Peter Luschny, Sep 29 2019

a(2*n) = A001790(n).
a(2*n+1) = A001803(n).
a(n) = a(n-1)*n^((-1)^(n+1))*2^valuation(n, 2) for n > 0. - Peter Luschny, Sep 29 2019

A090630 Greatest divisor d of n! such that d=m^k with k>1.

Original entry on oeis.org

1, 1, 1, 1, 8, 8, 144, 144, 576, 5184, 518400, 518400, 2073600, 2073600, 101606400, 914457600, 14631321600, 14631321600, 526727577600, 526727577600, 52672757760000, 221225582592000, 6373403688960000, 6373403688960000, 917770131210240000, 22944253280256000000, 3877578804363264000000

Offset: 0

Reinhard Zumkeller, Dec 13 2003

nonn

a(n) is a square for all n except n = 4, 5 and 21 (Wilke, 1981). - Amiram Eldar, Jun 09 2022

Charles R Greathouse IV, Table of n, a(n) for n = 0..500
Eric Weisstein's World of Mathematics, Perfect Powers.
Eric Weisstein's World of Mathematics, Factorial.
Kenneth M. Wilke, Problem 493, Pi Mu Epsilon Journal, Vol. 7, No. 4 (1981), p. 265; alternative link.
Index entries for sequences related to factorial numbers.

Cf. A011776, A060818, A060828, A251753.

f:= proc(n)
  local F,  k, d,r,s;
  F:= ifactors(n!)[2];
  r:= 1;
  for k from 2 to F[1][2] do
    r:= max(r, mul(f[1]^(k*floor(f[2]/k)),f=F))
  od:
r
end proc:
1,1,seq(f(n), n=2..100); # Robert Israel, Dec 08 2014

IsPower[n_] := If[n==1, True, GCD@@(Transpose[FactorInteger[n]][[2]])>1]; Table[Select[Divisors[n! ], IsPower][[ -1]], {n, 0, 25}]

a(n)=my(f=factor(n!),m=1); for(i=2,if(#f~,f[1,2]), m=max(factorback(concat(Mat(f[,1]), f[,2]\i*i)),m)); m \\ Charles R Greathouse IV, Dec 09 2014

a(n)= n!/A251753(n). - Robert G. Wilson v, Dec 08 2014

More terms from T. D. Noe, Oct 04 2004

A334907 Comtet's expansion of the e.g.f. (sqrt(1 + sqrt(8s)) - sqrt(1 - sqrt(8s)))/ sqrt(8s (1 - 8*s)).

Original entry on oeis.org

1, 5, 63, 1287, 36465, 1322685, 58503375, 3053876175, 183771489825, 12525477859125, 953725671273375, 80237355387564375, 7391465178302430225, 739967791738943292525, 79993069900054731795375, 9286937373235386442953375, 1152424501315118408602850625

Offset: 0

Petros Hadjicostas, May 15 2020

nonn

A special case of an integral in Comtet (1967, pp. 85-86) yields

Integral_{t=-oo..oo} dx/(x^2 + t^2)^(2*n) = Pi * a(n-1)/((n-1)! * 2^(3*n - 2) * t^(4*n-1)) for n >= 1 and t > 0. This integral also follows from a theorem in Moll (2002, p. 312, set a=1), but it requires the summation formula for a(n) shown below.

Louis Comtet, Fonctions génératrices et calcul de certaines intégrales, Publikacije Elektrotechnickog faculteta - Serija Matematika i Fizika, No. 181/196 (1967), 77-87; see pp. 81-83.
Petros Hadjicostas, Proof of the claim a(n) = n!*A063079(n+1)/A060818(n), 2020.
V. H. Moll, The evaluation of integrals: a personal story, Notices Amer. Math. Soc., 49 (No. 3, March 2002), 311-317.

Cf. A001790, A060818, A063079, A223549, A223550.

a(n) = binomial(4*n+2, 2*n+1)*n!/2^(n+1).
a(n) = n!*A063079(n+1)/A060818(n) = n!*A001790(2*n+1)/A060818(n) (see the link for a proof).
a(n) = n!*Sum_{j=0..n} 2^(n-2*j)*binomial(2*n+1,2*j)*binomial(2*j,j).
a(n) = 2^n*n!*Sum_{k=0..n} A223549(n,k)/A223550(n,k).
E.g.f.: 2/(sqrt(1 - 8*s) * (sqrt(1 + sqrt(8*s)) + sqrt(1 - sqrt(8*s)))).
E.g.f.: sqrt(2/(1 + sqrt(1 - 8*s))/(1 - 8*s)).
D-finite with recurrence (2*n+1)*a(n) -(4*n-1)*(4*n+1)*a(n-1)=0. - R. J. Mathar, May 25 2020

A063079 Bisection of A001790.

Original entry on oeis.org

1, 5, 63, 429, 12155, 88179, 1300075, 9694845, 583401555, 4418157975, 67282234305, 514589420475, 15801325804719, 121683714103007, 1879204156221315, 14544636039226909, 1804857108504066435

Offset: 1

N. J. A. Sloane, Aug 07 2001

Vincenzo Librandi, Table of n, a(n) for n = 1..200
Petros Hadjicostas, Proof of the claim A334907(n)/n! = a(n+1)/A060818(n), 2020.

Cf. A001790, A060818, A334907. Other bisection gives A061548.

seq(numer(binomial(2*n-3/2,-1/2)), n=1..20);

Numerator[Binomial[2Range[20]-3/2,-(1/2)]] (* Harvey P. Dale, Feb 27 2012 *)

Numerators of binomial(2*n-3/2, -1/2).

Because A334907(n)/n! = a(n+1)/A060818(n) for n >= 0, the o.g.f. of a(n+1)/A060818(n), for n >= 0, is (sqrt(1 + sqrt(8*s)) - sqrt(1 - sqrt(8*s)))/sqrt(8*s * (1 - 8*s)), which is the e.g.f. of A334907 (see the link above for a proof). - Petros Hadjicostas, May 16 2020

More terms from Vladeta Jovovic, Aug 07 2001

A232097 a(n) = least k such that 1+2+3+...+k (k-th triangular number) is a multiple of n!; a(n) = least k such that A232096(k) >= n.

Original entry on oeis.org

1, 3, 3, 15, 15, 224, 224, 4095, 76544, 512000, 9511424, 20916224, 410572799, 672358400, 2985984000, 1004293914624, 1004293914624, 78942076928000, 610877575397375, 83179139563520000, 490473044848410624, 6878928869130239999, 185974097225789210624, 1708887984313466880000, 68817755280574852890624

Offset: 1

Antti Karttunen, Nov 18 2013

nonn

a(n) = least k such that A232096(k) >= n.
Each A000217(a(n)) is divisible by A118381(n).
Each a(n) or a(n)+1 is divisible by 2*A060818(n) = A086117(n+1).
Each a(n) or a(n)+1 is divisible by A060828(n), and similarly for all the higher bases.
If we were instead searching for the first occurrence where A232096 gets a new distinct value, then we would have another sequence, b, which would start as: 1, 3, 4, 15, 32, 224, 575, 4095, ... as those distinct values do not appear in monotone order, being for n>=1, A232096(b(n)) = 1, 3, 2, 5, 4, 7, 6, 8, 9, 10, ...

			a(5) = 15 as binomial(15 + 1, 2) = 120 is the smallest binomial that is divisible by 5! = 120. - _David A. Corneth_, Mar 29 2021

Cf. A000217, A232096. A232101 gives the ratio A000217(a(n)) / n!

a(n) = { my(p = 2*n!, f = factor(p), res = oo); for(i = 2^(#f~-1), 2^#f~-1, b = binary(i); pr = prod(j = 1, #f~, f[j,1]^(b[j]*f[j, 2])); ipr = p/pr; for(j = -1, 0, c = lift(chinese(Mod(-1-j, ipr), Mod(j, pr))); if(c > 0, res = min(res, c)))); res } \\ David A. Corneth, Mar 29 2021

(define (A232097 n) (let ((increment (* 2 (A060818 n)))) (let loop ((k increment)) (cond ((>= (A232096 (- k 1)) n) (- k 1)) ((>= (A232096 k) n) k) (else (loop (+ k increment)))))))
;; Alternative, very naive and slow version:
(define (A232097v2 n) (let loop ((k 1)) (if (>= (A232096 k) n) k (loop (+ 1 k)))))

A242954 a(n) = Product_{i=1..n} A234957(i).

Original entry on oeis.org

1, 1, 1, 1, 4, 4, 4, 4, 16, 16, 16, 16, 64, 64, 64, 64, 1024, 1024, 1024, 1024, 4096, 4096, 4096, 4096, 16384, 16384, 16384, 16384, 65536, 65536, 65536, 65536, 1048576, 1048576, 1048576, 1048576, 4194304, 4194304, 4194304, 4194304, 16777216, 16777216, 16777216

Offset: 0

Tom Edgar, May 27 2014

nonn

This is the generalized factorial for A234957.

a(0) = 1 as it represents the empty product.

Tyler Ball, Tom Edgar, and Daniel Juda, Dominance Orders, Generalized Binomial Coefficients, and Kummer's Theorem, Mathematics Magazine, Vol. 87, No. 2, April 2014, pp. 135-143.

Cf. A054893, A060818, A060828, A234957.

S=[0]+[4^valuation(i,4) for i in [1..100]]
[prod(S[1:i+1]) for i in [0..99]]

a(n) = Product_{i=1..n} A234957(i).

a(n) = 4^(A054893(n)). - Vaclav Kotesovec, May 28 2014

A243757 a(n) = Product_{i=1..n} A060904(i).

Original entry on oeis.org

1, 1, 1, 1, 1, 5, 5, 5, 5, 5, 25, 25, 25, 25, 25, 125, 125, 125, 125, 125, 625, 625, 625, 625, 625, 15625, 15625, 15625, 15625, 15625, 78125, 78125, 78125, 78125, 78125, 390625, 390625, 390625, 390625, 390625, 1953125, 1953125, 1953125, 1953125, 1953125, 9765625

Offset: 0

Tom Edgar, Jun 10 2014

nonn

This is the generalized factorial for A060904.
a(0) = 1 as it represents the empty product.
a(n) is the largest power of 5 that divides n!, or the order of a 5-Sylow subgroup of the symmetric group of degree n. - David Radcliffe, Sep 03 2021

Reinhard Zumkeller, Table of n, a(n) for n = 0..1000
Tyler Ball, Tom Edgar, and Daniel Juda, Dominance Orders, Generalized Binomial Coefficients, and Kummer's Theorem, Mathematics Magazine, Vol. 87, No. 2, April 2014, pp. 135-143.

Cf. A027868, A060818, A060828, A060904, A242954.

a243757 n = a243757_list !! n
a243757_list = scanl (*) 1 a060904_list
-- Reinhard Zumkeller, Feb 04 2015

Table[Product[5^IntegerExponent[k, 5], {k, 1, n}], {n, 0, 20}] (* G. C. Greubel, Dec 24 2016 *)

a(n) = prod(k=1,n, 5^valuation(k,5)); \\ G. C. Greubel, Dec 24 2016

S=[0]+[5^valuation(i, 5) for i in [1..100]]
[prod(S[1:i+1]) for i in [0..99]]

a(n) = Product_{i=1..n} A060904(i).

a(n) = 5^(A027868(n)).

A348676 Triangle read by rows, T(n, k) = 2^(n - HammingWeight(k)), for 0 <= k <= n.

Original entry on oeis.org

1, 2, 1, 4, 2, 2, 8, 4, 4, 2, 16, 8, 8, 4, 8, 32, 16, 16, 8, 16, 8, 64, 32, 32, 16, 32, 16, 16, 128, 64, 64, 32, 64, 32, 32, 16, 256, 128, 128, 64, 128, 64, 64, 32, 128, 512, 256, 256, 128, 256, 128, 128, 64, 256, 128, 1024, 512, 512, 256, 512, 256, 256, 128, 512, 256, 256

Offset: 0

Peter Luschny, Oct 29 2021

			Triangle starts:
[0] 1;
[1] 2,   1;
[2] 4,   2,   2;
[3] 8,   4,   4,   2;
[4] 16,  8,   8,   4,   8;
[5] 32,  16,  16,  8,   16,  8;
[6] 64,  32,  32,  16,  32,  16,  16;
[7] 128, 64,  64,  32,  64,  32,  32,  16;
[8] 256, 128, 128, 64,  128, 64,  64,  32, 128;
[9] 512, 256, 256, 128, 256, 128, 128, 64, 256, 128;

Cf. A000120, A000079, A060818, A054243 (row gcd).

Cf. A348684, A348685, A348687.

HammingWeight := n -> add(i, i = convert(n, base, 2)):
A348676 := (n, k) -> 2^(n - HammingWeight(k)):
seq(seq(A348676(n, k), k = 0..n), n = 0..10);

Table[2^(n - DigitCount[k, 2, 1]), {n, 0, 10}, {k, 0, n}] // Flatten (* Amiram Eldar, Oct 30 2021 *)

cp's OEIS Frontend

A082907 A modified Pascal's triangle, read by rows, and modified as follows: binomial(n,j) is replaced by gcd(2^n, binomial(n,j)), i.e., the largest power of 2 dividing binomial(n,j).

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A220002 Numerators of the coefficients of an asymptotic expansion in even powers of the Catalan numbers.

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Sage

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A163590 Odd part of the swinging factorial A056040.

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A090630 Greatest divisor d of n! such that d=m^k with k>1.

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A334907 Comtet's expansion of the e.g.f. (sqrt(1 + sqrt(8*s)) - sqrt(1 - sqrt(8*s)))/ sqrt(8*s * (1 - 8*s)).

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A063079 Bisection of A001790.

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A232097 a(n) = least k such that 1+2+3+...+k (k-th triangular number) is a multiple of n!; a(n) = least k such that A232096(k) >= n.

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A334907 Comtet's expansion of the e.g.f. (sqrt(1 + sqrt(8s)) - sqrt(1 - sqrt(8s)))/ sqrt(8s (1 - 8*s)).