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A127964 Number of 0's in A127962(n). 3
0, 1, 2, 4, 5, 7, 8, 10, 14, 20, 29, 38, 49, 62, 82, 94, 98, 155, 172, 349, 853, 1307, 1768, 2902, 5249, 5344, 5638, 6194, 7238 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Apparently n such that (2^(2*n+3)+1)/3 is prime. - James R. Buddenhagen, Apr 14 2011

LINKS

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

FORMULA

a(n) = A023416(A000979(n)). - Michel Marcus, Nov 07 2013

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]], {x, 1, Length[a]}]; d (*Artur Jasinski*)

CROSSREFS

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

Sequence in context: A018519 A050054 A018371 * A269929 A085370 A006693

Adjacent sequences:  A127961 A127962 A127963 * A127965 A127966 A127967

KEYWORD

nonn

AUTHOR

Artur Jasinski, Feb 09 2007

EXTENSIONS

a(22)-a(29) from Vincenzo Librandi, Mar 31 2012

STATUS

approved

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Last modified February 21 16:28 EST 2018. Contains 299414 sequences. (Running on oeis4.)