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A223523 Triangle S(n, k) by rows: coefficients of 2^((n-1)/2))*(x^(1/2)*d/dx)^n, where n = 1, 3, 5, ... 25
1, 3, 2, 15, 20, 4, 105, 210, 84, 8, 945, 2520, 1512, 288, 16, 10395, 34650, 27720, 7920, 880, 32, 135135, 540540, 540540, 205920, 34320, 2496, 64, 2027025, 9459450, 11351340, 5405400, 1201200, 131040, 6720, 128 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Triangle S(n,n-k) by rows: coefficients of 2^n * |L(n,1/2,x)|, with L the generalized Laguerre polynomials.

LINKS

Table of n, a(n) for n=1..36.

FORMULA

T(n, k) = 2^n * n!/(n-k)! * C(n+1/2, k), n>=0, k<=n.

EXAMPLE

Triangle begins:

1;

3, 2;

15, 20, 4;

105, 210, 84, 8;

945, 2520, 1512, 288, 16;

10395, 34650, 27720, 7920, 880, 32;

135135, 540540, 540540, 205920, 34320, 2496, 64;

.

.

Expansion takes the form:

2^0 (x^(1/2)*d/dx)^1 = 1*x^(1/2)*d/dx.

2^1 (x^(1/2)*d/dx)^3 = 3*x^(1/2)*d^2/dx^2 + 2*x^(3/2)*d^3/dx^3.

2^2 (x^(1/2)*d/dx)^5 = 15*x^(1/2)*d^3/dx^3 + 20*x^(3/2)*d^4/dx^4 + 4*x^(5/2)*d^5/dx^5.

MAPLE

a[0]:= f(x):

for i from 1 to 20 do

a[i]:= simplify(2^((i+1)mod 2)*x^(1/2)*(diff(a[i-1], x$1)));

end do:

for j from 1 to 10 do

b[j]:=a[2j-1];

end do;

CROSSREFS

Cf. A223168-A223172.

Rows includes odd rows of A223168.

Rows includes absolute values of A098503 from right to left of the triangular form.

Sequence in context: A218969 A185973 A051917 * A133932 A111999 A190961

Adjacent sequences:  A223520 A223521 A223522 * A223524 A223525 A223526

KEYWORD

nonn,tabl

AUTHOR

Udita Katugampola, Mar 21 2013

STATUS

approved

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Last modified April 24 12:56 EDT 2014. Contains 240983 sequences.