a(n)=(1/2)*Sum{|d(i)-e(i)|} where Sum{d(i)*7^i} is the base 7 representation of n and e(i) are the digits d(i) in reverse order.
A037893
a(n)=(1/2)*Sum{|d(i)-e(i)|} where Sum{d(i)*7^i} is the base 7 representation of n and e(i) are the digits d(i) in reverse order.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =1a(7) =0a(8) =1a(9) =2a(10) =3a(11) =4a(12) =5a(13) =2a(14) =1a(15) =0a(16) =1a(17) =2a(18) =3a(19) =4a(20) =3a(21) =2a(22) =1a(23) =0a(24) =1a(25) =2a(26) =3a(27) =4a(28) =3a(29) =2
External references
- oeis: A037893