cp's OEIS Frontend

A077718 Primes which can be expressed as sum of distinct powers of 4.

%I A077718 #17 Sep 06 2018 19:28:23
%S A077718 5,17,257,277,337,1093,1109,1297,1301,1361,4177,4357,4373,4421,5189,
%T A077718 5381,5393,5441,16453,16657,16661,17477,17489,17669,17681,17729,17749,
%U A077718 20549,20753,21521,21569,21589,21841,65537,65557,65617,65809,66629
%N A077718 Primes which can be expressed as sum of distinct powers of 4.
%C A077718 Primes whose base 4 representation contains only zeros and 1's.
%C A077718 As a subsequence of primes in A000695, these could be called Moser-de Bruijn primes. See also A235461 for those terms whose base 4 representation also represents a prime in base 2. - _M. F. Hasler_, Jan 11 2014
%H A077718 Robert Israel, <a href="/A077718/b077718.txt">Table of n, a(n) for n = 1..10000</a>
%p A077718 f:= proc(n) local L,x;
%p A077718   L:= convert(n,base,2);
%p A077718   x:= 1+add(L[i]*4^i,i=1..nops(L));
%p A077718   if isprime(x) then x fi
%p A077718 end proc:
%p A077718 map(f, [$1..1000]); # _Robert Israel_, Sep 06 2018
%t A077718 Select[Prime[Range[6650]],Max[IntegerDigits[#,4]]<=1&] (* _Jayanta Basu_, May 22 2013 *)
%o A077718 (PARI) for(i=1,999,isprime(b=vector(#b=binary(i),j,4^(#b-j))*b~)&&print1(b",")) \\ - _M. F. Hasler_, Jan 12 2014
%Y A077718 Cf. A020449, A000695, A077717, A077719, A077720, A077721, A077722.
%K A077718 nonn
%O A077718 1,1
%A A077718 _Amarnath Murthy_, Nov 19 2002
%E A077718 More terms from _Sascha Kurz_, Jan 03 2003