Some numbers remain numbers when turned upside down (using digits 0125689, with no final 0's): 1, 2, 5, 6, 8, 9, 11, 12, … etc

IF a₁=1, a₂=2, a₃=5,... a₈=12,…, etc

a.Evaluate a₁₀₀
b. Evaluate a₁₀₀₀
c. If a_n= 888, what is n?

(In reply to re: Direct Basic solution......corrections... by Ady TZIDON)

Well, that's what I get for showing off.  I guess I should have used my procedure with Charlie's known answers.  Or checked my work.  Or both.

Posted by Steve Herman on 2014-04-12 11:41:15