A356405 Primes that are the sum of a set of numbers taken from 1 and 2^(2^k) for k >= 0.

2, 3, 5, 7, 17, 19, 23, 257, 263, 277, 65537, 65539, 65543, 65557, 65809, 4294967569, 4295032837, 4295033107, 340282366920938463463374607431768211729, 340282366920938463463374607431768277267, 340282366920938463463374607436063179013, 340282366920938463481821351505477763347

Offset

1,1

Comments

Primes in whose binary expansion sum_i d_i 2^i, d_i = 1 only if i is in A131577.

Links

Robert Israel, Table of n, a(n) for n = 1..34

Example

a(6) = 19 is a term because 19 = 1 + 2^(2^0) + 2^(2^2).

Maple

exps:= [0, seq(2^i, i=0..10)]:
S:= combinat:-powerset(exps):
select(isprime, map(proc(t) local i; add(2^i, i=t) end proc, S));

Crossrefs

Cf. A131577.

Sequence in context: A214588 A089968 A164060 * A113029 A090432 A301918

Adjacent sequences: A356402 A356403 A356404 * A356406 A356407 A356408

Keyword

nonn,base

Author

J. M. Bergot and Robert Israel, Aug 05 2022

Status

approved