1573376

Appears in sequences

• a(n) is the sum of all integers from 2^(n-2)+1 to 2^(n-1).at n=10A049775
• Number of periodic palindromic structures of length n using a maximum of two different symbols.at n=41A056503
• Relates row sums of Pascal's triangle to expansion of cos(x)/exp(x).at n=20A100216
• a(n) = ((2^n)*((2^n)+1) - (2^(n-1))*((2^(n-1))+1))/2, a(1)=3.at n=10A158561