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%I #22 Mar 20 2019 17:11:10
%S 1,7,8,5,5,8,2,1,2,2,2,4,5,8,2,4,4
%N a(n) is the first digit to appear n times in succession in a power of 3.
%o (Python)
%o def A215733(n):
%o ....l, x = [str(d)*n for d in range(10)], 1
%o ....for m in range(10**9):
%o ........s = str(x)
%o ........for k in range(10):
%o ............if l[k] in s:
%o ................return k
%o ........x *= 3
%o ....return 'search limit reached'
%o # _Chai Wah Wu_, Dec 17 2014
%Y Cf. A215727, A045875, A215732.
%K nonn,base,more
%O 1,2
%A _V. Raman_, Aug 22 2012
%E a(12) from _Chai Wah Wu_, Dec 17 2014
%E a(13)-a(14) from _Giovanni Resta_, Apr 20 2016
%E a(15) from _Bert Dobbelaere_, Mar 04 2019
%E a(16)-a(17) from _Bert Dobbelaere_, Mar 20 2019
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