0,2

a(n) =(2^(n+2)-1)*n*(n+1)/2 =A059672(n)+A059938(n) =a(n-1)*2*(n+1)/(n-1)+n(n+1)/2

a(2)=45 since binary sum of 1100 + 1010 + 1001 + 0110 + 0101 + 0011 is 12 + 10 + 9 + 6 + 5 + 3=45.

Cf. A059672, A059673, A059938.

Sequence in context: A156374 A153492 A107125 this_sequence A099842 A115194 A062274

Adjacent sequences: A059934 A059935 A059936 this_sequence A059938 A059939 A059940

nonn

Henry Bottomley (se16(AT)btinternet.com), Feb 13 2001