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A352889
Number of runs in the binary expansion of A109812(n).
4
1, 2, 2, 1, 2, 3, 4, 2, 2, 3, 4, 2, 3, 2, 2, 1, 2, 3, 4, 3, 4, 3, 4, 5, 4, 3, 2, 1, 2, 4, 5, 4, 3, 4, 3, 4, 5, 4, 3, 2, 3, 4, 3, 2, 3, 4, 4, 3, 4, 2, 3, 4, 3, 2, 3, 4, 5, 6, 4, 6, 5, 4, 5, 4, 6, 3, 4, 2, 3, 4, 3, 4, 3, 2, 2, 1, 4, 5, 4, 5, 6, 5, 4, 3, 4, 5, 4, 3, 4, 5, 6, 7, 6, 5, 6, 4, 5, 2, 5, 4, 4, 3, 2, 3, 4
OFFSET
1,2
FORMULA
a(n) = A005811(A109812(n)).
EXAMPLE
n A109812(n) [in base-2] a(n) = number of runs
-----+-------------------------------------------------
1 | 1 [1], 1
2 | 2 [10], 2
3 | 4 [100], 2
4 | 3 [11], 1
5 | 8 [1000], 2
6 | 5 [101], 3
7 | 10 [1010], 4
8 | 16 [10000], 2
9 | 6 [110], 2
10 | 9 [1001], 3
11 | 18 [10010], 4
PROG
(PARI)
v109812 = readvec("b109812_to10e5.txt"); \\ Prepared from b-file data with gawk ' { print $2 } '
up_to = #v109812;
A109812(n) = v109812[n];
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Apr 07 2022
STATUS
approved