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A127963 Number of 1's in A127962(n). 3
2, 3, 4, 6, 7, 9, 10, 12, 16, 22, 31, 40, 51, 64, 84, 96, 100, 157, 174, 351, 855, 1309, 1770, 2904, 5251, 5346, 5640, 6196, 7240 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

a(n) = A000120(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, 1]], {x, 1, Length[a]}]; d (* Artur Jasinski, Feb 09 2007 *)

CROSSREFS

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

Sequence in context: A111333 A047701 A164528 * A031403 A189578 A190859

Adjacent sequences:  A127960 A127961 A127962 * A127964 A127965 A127966

KEYWORD

nonn,base

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 October 23 18:36 EDT 2018. Contains 316529 sequences. (Running on oeis4.)