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 A045716 a(n) is the binary order (A029837) of the n-th primorial number, A002110(n). 7
 1, 3, 5, 8, 12, 15, 19, 24, 28, 33, 38, 43, 49, 54, 60, 65, 71, 77, 83, 89, 96, 102, 108, 115, 121, 128, 135, 141, 148, 155, 162, 169, 176, 183, 190, 198, 205, 212, 220, 227, 235, 242, 250, 257, 265, 273, 280, 288, 296, 304, 312, 319, 327, 335, 343, 351, 359 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS These orders determine the maximal numbers of unitary divisors valid for integers in given binary order ranges (see A046971). LINKS Michael De Vlieger, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A054850(n)+1, n >= 2. a(n) = A070939(A002110(n)) for n>1. - Jachym Barvinek, Mar 22 2018 EXAMPLE The sixth primorial number is 2*3*5*7*11*13 = 30030, which is in the interval [16385, 32768] = [2^14 + 1, 2^15], so its binary order is a(6)=15. [corrected by Jon E. Schoenfield, May 13 2018] MATHEMATICA Table[Ceiling@ Log2[Times @@ Prime@ Range@ n], {n, 57}] (* Michael De Vlieger, Feb 05 2017 *) PROG (PARI) a(n)=logint(prod(i=1, n, prime(i))-1, 2)+1 \\ Charles R Greathouse IV, Feb 06 2017 CROSSREFS Cf. A029837, A002110, A046971, A054850. Sequence in context: A218485 A310029 A310030 * A236203 A122539 A310031 Adjacent sequences:  A045713 A045714 A045715 * A045717 A045718 A045719 KEYWORD nonn AUTHOR STATUS approved

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Last modified June 16 10:03 EDT 2019. Contains 324152 sequences. (Running on oeis4.)