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A127965 Number of bits in A127962(n). 3
2, 4, 6, 10, 12, 16, 18, 22, 30, 42, 60, 78, 100, 126, 166, 190, 198, 312, 346, 700, 1708, 2616, 3538, 5806, 10500, 10690, 11278, 12390, 14478 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Equals A127964(n) + A127963(n).

LINKS

Table of n, a(n) for n=1..29.

FORMULA

a(n) = 1+floor[ log_2(A000979(n)) ] = 1+ floor[log_2(2^A000978(n)+1) - A020857] = A000978(n)-1 . - R. J. Mathar, Feb 01 2008

MATHEMATICA

b = {}; Do[c = 1 + Sum[2^(2n - 1), {n, 1, x}]; If[PrimeQ[c], AppendTo[b, c]], {x, 0, 1000}]; a = {}; Do[AppendTo[a, FromDigits[IntegerDigits[b[[x]], 2]]], {x, 1, Length[b]}]; d = {}; Do[AppendTo[d, DigitCount[a[[x]], 10, 0]+DigitCount[a[[x]], 10, 1]], {x, 1, Length[a]}]; d (*Artur Jasinski*)

CROSSREFS

Cf. A127962, A127963, A127964, A127961, A000979, A000978, A124400, A126614, A127955, A127956, A127957, A127958, A127936.

Sequence in context: A075728 A146886 A006093 * A117891 A262935 A178539

Adjacent sequences:  A127962 A127963 A127964 * A127966 A127967 A127968

KEYWORD

nonn

AUTHOR

Artur Jasinski, Feb 09 2007

EXTENSIONS

a(22)-a(29) from Vincenzo Librandi, Mar 30 2012

STATUS

approved

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Last modified February 24 18:24 EST 2018. Contains 299628 sequences. (Running on oeis4.)