Subsidiary sequence: Sum of the numbers formed by deleting all possible strings touching one end ( containing at least one of the LSB or MSB). a(123) = 123 + 12 + 1 + 23 + 3 = 162. a(1234) = 1 + 12 + 123 + 1234 + 234 + 34 + 4 = 1642.

This allows leading zeros are after deletion. If these are forbidden, the first change would be a(101) = 21 instead of 22. - Franklin T. Adams-Watters, Jul 27 2006