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A131765 Series reversion of x(1-5x)/(1-x) . 2
1, 4, 36, 404, 5076, 68324, 963396, 14046964, 210062196, 3204118724, 49656709476, 779690085204, 12376867734036, 198301332087204, 3202580085625476, 52080967814444724, 852103170531254196, 14016301507253656964 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

The Hankel transform of this sequence is 20^C(n+1,2) .

FORMULA

a(n) = Sum_{k, 0<=k<=n}A086810(n,k)*4^k .

a(n)=sum{k=0..n, C(n+k,2k)*A000108(k)*(-1)^(n-k)*5^k}; a(n)=sum{k=0..n, C(n+k,2k)*A000108(k)*(4^(k+1)+(-1)^k)/5}. [From Paul Barry (pbarry(AT)wit.ie), Sep 08 2009]

CROSSREFS

Sequence in context: A019999 A002894 A202828 * A132864 A052700 A167540

Adjacent sequences:  A131762 A131763 A131764 * A131766 A131767 A131768

KEYWORD

nonn

AUTHOR

Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Oct 29 2007

EXTENSIONS

Extra terms added. Paul Barry (pbarry(AT)wit.ie), Sep 08 2009

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Last modified February 17 23:58 EST 2012. Contains 206085 sequences.