0,2

a(n) = n*( n*(2n+1)+1 + n*(2n+1)+2 + ... + n*(2n+1)+2n )

a(n) = n*A000290(n); n*a(n) = A014105(n)^2

a(3) = 147 since 147 = 3*7^2

Sequence in context: A088064 A080812 A116169 this_sequence A006974 A007681 A115366

Adjacent sequences: A084364 A084365 A084366 this_sequence A084368 A084369 A084370

easy,nonn

Charlie Marion (charliem(AT)bestweb.net), Jun 22 2003