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A297778
Number of distinct runs in base-10 digits of n.
3
1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2
OFFSET
1,10
COMMENTS
Every positive integers occurs infinitely many times. See A297770 for a guide to related sequences. A043562(n) = a(n) for n=1..100, but not for n=101.
LINKS
EXAMPLE
14! in base-10: 2,7,0,0,1,7,3,0,1,3,0,0; ten runs, of which 6 are distinct, so that a(14!) = 6.
MATHEMATICA
b = 10; s[n_] := Length[Union[Split[IntegerDigits[n, b]]]]
Table[s[n], {n, 1, 200}]
CROSSREFS
Cf. A043562 (number of runs, not necessarily distinct), A297770.
Sequence in context: A297777 A043536 A043561 * A043562 A043537 A047726
KEYWORD
nonn,base,easy
AUTHOR
Clark Kimberling, Feb 03 2018
STATUS
approved