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 A054248 Binary entropy: a(n) = n + min { a(k)+a(n-k) : 1 <= k <= n-1 }. 4
 1, 2, 6, 8, 13, 16, 21, 24, 30, 34, 40, 44, 50, 54, 60, 64, 71, 76, 83, 88, 95, 100, 107, 112, 119, 124, 131, 136, 143, 148, 155, 160, 168, 174, 182, 188, 196, 202, 210, 216, 224, 230, 238, 244, 252, 258, 266, 272, 280, 286, 294, 300, 308, 314 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES D. E. Knuth, The Art of Computer Programming. Addison-Wesley, Reading, MA, Vol. 3, p. 374. LINKS Alois P. Heinz, Table of n, a(n) for n = 1..10000 Hsien-Kuei Hwang, S. Janson, T.-H. Tsai, Exact and asymptotic solutions of the recurrence f(n) = f(floor(n/2)) + f(ceiling(n/2)) + g(n): theory and applications, Preprint 2016. Hsien-Kuei Hwang, S. Janson, T.-H. Tsai, Exact and Asymptotic Solutions of a Divide-and-Conquer Recurrence Dividing at Half: Theory and Applications, ACM Transactions on Algorithms, 13:4 (2017), #47; DOI: 10.1145/3127585. FORMULA a(n) = A123753(n-1) - (n-1) mod 2. - Peter Luschny, Nov 30 2017 MAPLE A054248 := proc(n) local i, j; option remember; if n<=2 then n else j := 10^10; for i from 1 to n-1 do if A054248(i)+A054248(n-i) < j then j := A054248(i)+A054248(n-i); fi; od; n+j; fi; end; # second Maple program: a:= proc(n) option remember; `if`(n<3, n,       n + min(seq(a(k)+a(n-k), k=1..n/2)))     end: seq(a(n), n=1..80);  # Alois P. Heinz, Aug 29 2015 MATHEMATICA a[n_] := n + n IntegerLength[n, 2] - 2^IntegerLength[n, 2] + Mod[n, 2]; Table[a[n], {n, 1, 54}] (* Peter Luschny, Dec 02 2017 *) PROG (Python) def A054248(n):     s, i, z = n - (n-1) % 2, n-1, 1     while 0 <= i: s += i; i -= z; z += z     return s print([A054248(n) for n in range(1, 55)]) # Peter Luschny, Nov 30 2017 CROSSREFS Cf. A003314, A123753. Sequence in context: A168247 A229056 A186703 * A038108 A294862 A087327 Adjacent sequences:  A054245 A054246 A054247 * A054249 A054250 A054251 KEYWORD nonn AUTHOR N. J. A. Sloane, May 04 2000 STATUS approved

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Last modified December 5 20:40 EST 2019. Contains 329777 sequences. (Running on oeis4.)