A111099 - OEIS

%I #8 Apr 29 2016 05:25:50

%S 0,1,2,4,9,20,45,105,246,583,1393,3355,8133,19825,48554,119412,294761,

%T 729980,1813107,4515225,11271198,28196896,70679137,177487714,

%U 446446560,1124706145,2837445500,7167878628,18129622761,45907772900,116372614251

%N Sum of even Fermat coefficients rounded to nearest integer.

%H P. A. Piza, <a href="http://www.jstor.org/stable/3029103">Fermat coefficients</a>, Math. Mag., 27 (1954), 141-146.

%F Following Piza's definition for the Fermat coefficients: (n:c)=binomial(2n-c, c-1)/c, a(n)= Round( sum_{0<c<=n & c even} (n:c) ).

%p FermatCoeff:=(n,c)->binomial(2*n-c,c-1)/c:

%p seq(round(add(FermatCoeff(n,2*r),r=1..floor(n/2))),n=1..40);

%K nonn

%O 1,3

%A Pab Ter (pabrlos2(AT)yahoo.com), Oct 13 2005