A333878 - OEIS

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A333878

a(n) is the number of primes 2^(n-1) <= p < 2^n with minimal Hamming weight A091935(n-1) in this interval.

1, 1, 2, 1, 2, 3, 3, 1, 4, 2, 3, 2, 2, 2, 4, 1, 3, 4, 5, 3, 2, 1, 5, 1, 32, 2, 5, 2, 2, 8, 6, 37, 5, 3, 4, 2, 3, 2, 2, 57, 3, 5, 52, 1, 5, 3, 7, 63, 1, 2, 5, 1, 5, 2, 6, 87, 6, 99, 2, 3, 2, 1, 2, 102, 2, 3, 5, 3, 6, 2, 2, 2, 5, 2, 7, 1, 3, 2, 3, 1, 6, 2, 4, 3, 3

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OFFSET

2,3

LINKS

Giovanni Resta, Table of n, a(n) for n = 2..1000

MATHEMATICA

a[2] = 1; a[n_] := Block[{c = 0, nb = 0}, While[c == 0, c = Count[ 2^(n-1) + 1 + Total /@ Subsets[ 2^Range[n - 2], {nb}], x_ /; PrimeQ[x]]; nb++]; c]; Array[a, 90, 2] (* Giovanni Resta, Apr 09 2020 *)

CROSSREFS

Cf. A091935, A091936, A333876, A333879.

Sequence in context: A140530 A202191 A052250 * A099569 A191579 A097724

Adjacent sequences: A333875 A333876 A333877 * A333879 A333880 A333881

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Apr 08 2020

EXTENSIONS

Terms a(35) and beyond from Giovanni Resta, Apr 09 2020

STATUS

approved