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%I #26 May 19 2023 11:05:44
%S 10111,1011001,1100101,10010101,10100011,101001001,1000001011,
%T 1000010101,1010000011,1100010001,10000001101,10001000011,10001001001,
%U 10001100001,10100000011,10100001001,11000000101,11001000001
%N Primes made up of 0's and four 1's only.
%C Intersection of A062339 and A020449. Subsequence of A235154. - _Felix Fröhlich_, Nov 19 2014
%C Primes that are the sum of four distinct powers of ten (A038446). - _Jeppe Stig Nielsen_, May 18 2023
%H Jeppe Stig Nielsen, <a href="/A157711/b157711.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from T. D. Noe)
%p for d from 4 to 18 do for c from 0 to 2^d-1 do bdgs := convert(c,base,2) ; if add(i,i=bdgs) = 3 then p := 10^d+add(op(i,bdgs)*10^(i-1),i=1..nops(bdgs)) ; if isprime(p) then printf("%d,",p) ; fi; fi; od: od: # _R. J. Mathar_, Mar 06 2009
%t Flatten[Select[FromDigits/@Permutations[Join[{1,1,1,1},PadRight[{},7,0]]],PrimeQ]] // Union (* _Harvey P. Dale_, May 09 2019 *)
%o (PARI) for(n=0, 10, forprime(p=10^n, (10^(n+1)-1)/9, if(vecmax(digits(p))==1, if(sumdigits(p)==4, print1(p, ", "))))) \\ _Felix Fröhlich_, Nov 19 2014
%o (PARI) my(M=20);for(i=3, M, for(j=2,i-1, for(k=1, j-1, my(p=10^i+10^j+10^k+1); isprime(p)&&print1(p,", ")))) \\ _Jeppe Stig Nielsen_, May 18 2023
%Y Cf. A038446.
%Y Cf. A020449, A062339, A235154.
%K nonn,base
%O 1,1
%A _Lekraj Beedassy_, Mar 04 2009
%E Extended by numerous authors, Mar 06 2009
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