a(n) = ((2^n+1)^n - (2^n-1)^n)/2.A172340a(n) = ((2^n+1)^n - (2^n-1)^n)/2.Terms a(0) =1a(1) =8a(2) =193a(3) =16448a(4) =5253121a(5) =6447694208External referencesoeis: A172340