Position of the last occurrence of n digits in the number Pi that do not occur earlier.
1, 33, 606, 8554, 99847, 1369561, 14118308
0
For instance, the single digit “0” does not occur until the 33rd digit of Pi; the two digits “68” finally occur starting at position 606 in Pi; the three digits “483” finally appear starting at position 8554 in Pi. It is unknown whether the n-th term exists for all n.
T. D. Noe, Plot of 7 terms
(Mma) d = RealDigits[Pi, 10, 200000][[1]]; Table[nn = 10^pow; found = 0; cnt = Table[0, {nn}]; n = 0; While[found < nn, n++; q = FromDigits[Take[d, {n, n + pow - 1}]]; If[cnt[[q + 1]] == 0, cnt[[q + 1]] = 1; found++]]; n, {pow, 0, 4}]
nonn,base,hard
T. D. Noe, Jul 20 2015