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A228451
Recurrence: a(2n) = a(n), a(2n+1) = a(n) + 2n + 1, with a(0) = 0, a(1) = 1.
2
0, 1, 1, 4, 1, 6, 4, 11, 1, 10, 6, 17, 4, 17, 11, 26, 1, 18, 10, 29, 6, 27, 17, 40, 4, 29, 17, 44, 11, 40, 26, 57, 1, 34, 18, 53, 10, 47, 29, 68, 6, 47, 27, 70, 17, 62, 40, 87, 4, 53, 29, 80, 17, 70, 44, 99, 11, 68, 40, 99, 26, 87, 57, 120, 1, 66, 34, 101, 18, 87, 53, 124, 10, 83, 47, 122, 29, 106, 68
OFFSET
0,4
COMMENTS
Unique values are 0,1,4,6,10,11,17,18,26,27,29,34,40,47,53,57,62,68...
FORMULA
For m>0, a(2^m+1) = 2^m+2, a(2^m+2) = 2^(m-1)+2, a(2^m+3) = 3*2^m+5, a(2^m+2^(m-1)) = 4, a(2^m-1) = 2^(m+1) - m - 2.
PROG
(PARI) a(n)=if(n<2, n==1, if(n%2, n+a(n-1), a(n/2)))
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Ralf Stephan, Oct 27 2013
EXTENSIONS
Name corrected by Gionata Neri, Mar 27 2019
STATUS
approved