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A227737
n occurs as many times as there are runs in binary representation of n.
9
1, 2, 2, 3, 4, 4, 5, 5, 5, 6, 6, 7, 8, 8, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 14, 14, 15, 16, 16, 17, 17, 17, 18, 18, 18, 18, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 24, 24, 25, 25, 25, 26, 26, 26, 26
OFFSET
1,2
COMMENTS
a(n) = the least integer k such that A173318(k) >= n, which implies that each n occurs A005811(n) times.
Although as such quite uninteresting, this sequence is useful for computing irregular tables like A101211, A227736, A227738 and A227739.
LINKS
EXAMPLE
1 has one run in its binary representation "1", thus 1 occurs once.
2 has two runs in its binary representation "10", thus 2 occurs twice.
3 has one run in its binary representation "11", thus 3 occurs only once.
4 has two runs in its binary representation "100", thus 4 occurs twice.
5 has three runs in its binary representation "101", thus 5 occurs three times.
The sequence thus begins as 1, 2,2, 3, 4,4, 5,5,5, ...
MATHEMATICA
Table[ConstantArray[n, Length@ Split@ IntegerDigits[n, 2]], {n, 26}] // Flatten (* Michael De Vlieger, May 09 2017 *)
Table[PadRight[{}, Length[Split[IntegerDigits[n, 2]]], n], {n, 40}]//Flatten (* Harvey P. Dale, Jul 23 2021 *)
PROG
(Scheme with Antti Karttunen's IntSeq-library) (define A227737 (LEAST-GTE-I 1 1 A173318))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Jul 25 2013
STATUS
approved