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%I #7 Feb 02 2018 03:53:28
%S 1,1,1,1,1,1,2,1,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,1,2,2,
%T 2,2,2,2,2,1,2,2,2,2,2,2,2,1,2,2,3,3,3,3,3,2,1,2,2,2,2,2,3,2,2,3,3,3,
%U 3,3,2,3,2,3,3,3,3,2,3,3,2,3,3,3,2,3
%N Number of distinct runs in base-7 digits of n.
%C Every positive integers occurs infinitely many times. See A297770 for a guide to related sequences.
%H Clark Kimberling, <a href="/A297775/b297775.txt">Table of n, a(n) for n = 1..10000</a>
%e 1234567 in base-7: 1,3,3,3,1,2,1,5; six runs, of which 4 are distinct, so that a(1234567) = 4.
%t b = 7; s[n_] := Length[Union[Split[IntegerDigits[n, b]]]]
%t Table[s[n], {n, 1, 200}]
%Y Cf. A043559 (number of runs, not necessarily distinct), A297770, A043534.
%K nonn,base,easy
%O 1,7
%A _Clark Kimberling_, Jan 27 2018