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A111531 Row 4 of table A111528. 12
1, 1, 6, 46, 416, 4256, 48096, 591536, 7840576, 111226816, 1680157056, 26918720896, 455971214336, 8143926373376, 153013563734016, 3017996904928256, 62369444355076096, 1348096649995841536, 30426167700424728576, 715935203128235401216 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..19.

FORMULA

G.f.: (1/4)*Log(Sum_{n>=0} (n+3)!/3!*x^n) = Sum_{n>=1} a(n)*x^n/n.

G.f.: A(x) = 1/(1+4*x - 5*x/(1+5*x - 6*x/(1+6*x -... (continued fraction).

a(n)=Sum_{k, 0<=k<=n}4^(n-k)*A089949(n,k) . - Philippe Deléham, Oct 16 2006

G.f.: G(0)/2, where G(k)= 1 + 1/(1 - x*(k+1)/(x*(k-1) + 1/G(k+1))); (continued fraction). - Sergei N. Gladkovskii, Jun 05 2013

G.f.: W(0)/4 + 3/4, where W(k) = 1 - x*(k+4)/( x*(k+4) - 1/(1 - x*(k+2)/( x*(k+2) - 1/W(k+1) ))); (continued fraction). - Sergei N. Gladkovskii, Aug 26 2013

EXAMPLE

(1/4)*Log(1 + 4*x + 20*x^2 + 120*x^3 +... + (n+3)!/3!*x^n +...)

= x + 6/2*x^2 + 46/3*x^3 + 416/4*x^4 + 4256/5*x^5 +...

PROG

(PARI) {a(n)=if(n<0, 0, if(n==0, 1, (n/4)*polcoeff(log(sum(m=0, n, (m+3)!/3!*x^m) +x*O(x^n)), n)))}

for(n=0, 20, print1(a(n), ", "))

CROSSREFS

Cf: A111528 (table), A104980 (row 1), A111529 (row 2), A111530 (row 3), A111532 (row 5), A111533 (row 6), A111534 (diagonal).

Sequence in context: A190005 A084772 A199563 * A052781 A049378 A218497

Adjacent sequences:  A111528 A111529 A111530 * A111532 A111533 A111534

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Aug 06 2005

STATUS

approved

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Last modified December 21 08:32 EST 2014. Contains 252299 sequences.