A130586 - OEIS

%I #12 May 18 2019 16:57:59

%S 1,3,9,19,65,75,385,531,1545,2115,10241,8283,49153,49539,131145,

%T 262675,1048577,788043,4718593,4196435,12583305,20981763,92274689,

%U 67117659,335544385,402702339,1207961097,1610662291,7516192769,4295100555

%N Row sums of triangle A130585.

%C A130584 row sums = A001792, the binomial transform of [1,2,3,...]: (1, 3, 8, 20, 48, 112, ...).

%F Row sums of A130585.

%F a(n-1) = Sum_{d|n} phi(n/d)*2^(n/d - 1). [_Olivier Gérard_, Jan 01 2012]

%e a(3) = 19 = sum of row 3 terms of A130585: (4 + 7 + 6 + 2).

%t Table[Plus@@Map[Function[d,EulerPhi[(n+1)/d] 2^((n+1)/d-1)],Divisors[n+1]],{n,0,30}] (* _Olivier Gérard_, Jan 01 2012 *)

%Y Cf. A130585, A001792, A130584.

%K nonn

%O 0,2

%A _Gary W. Adamson_, Jun 06 2007

%E More terms from _Olivier Gérard_, Jan 01 2012