Problem 551

[Bordimor]

I think the statement of this problem is wrong

its says for n >= 1, an is the sum of the digits of all preceding terms.
so for n = 6 its should be 1+1+2+4+8+16 = 32 but the result example says 23 and going on the next value should be 64 but the problem says that is 38

i dont know if its an error in the statement or in the solutions value, also the result for n = 10^15 its a little big for get the result

[bruce_love]

Instead of adding $16$ you add the "digits of" $16$.
$1+1+2+4+8+(1+6) = 23$

[Bordimor]

OH i see it now, thanks.