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%I #2 Mar 30 2012 17:36:01
%S 1,2,4,6,10,14,22,22,30,46,74,94,90,102,130,170,198,222,290,350,474,
%T 650,730,734,746,838,962,1214,2138,2582,1890,1830,2526,3498,4746,6842,
%U 5098,6358,8178,10634,8650,9782,13634,14438,17178,20202,22170,21422,16298
%N Sum of the numbers of unitary divisors of the binomial coefficients C[n,k], k=0..n.
%C Row sums of the triangle A103444.
%e a(3)=6 because the divisors of 1,3,3,1 are {1},{1,3},{1,3},{1}, respectively, all of which are unitary.
%p with(numtheory):unitdiv:=proc(n) local A, k: A:={}: for k from 1 to tau(n) do if gcd(divisors(n)[k],n/divisors(n)[k])=1 then A:=A union {divisors(n)[k]} else A:=A fi od end: T:=proc(n,k) if k<=n then nops(unitdiv(binomial(n,k))) else 0 fi end: for n from 0 to 50 do b[n]:=[seq(T(n,k),k=0..n)] od: seq(sum(b[n][j],j=1..n+1),n=0..50);
%Y Cf. A103444.
%K nonn
%O 0,2
%A _Emeric Deutsch_, Feb 06 2005
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