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 A157711 Primes made up of 0's and four 1's only. 4
 10111, 1011001, 1100101, 10010101, 10100011, 101001001, 1000001011, 1000010101, 1010000011, 1100010001, 10000001101, 10001000011, 10001001001, 10001100001, 10100000011, 10100001001, 11000000101, 11001000001 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A062339 and A020449. Subsequence of A235154. - Felix Fröhlich, Nov 19 2014 Primes that are the sum of four distinct powers of ten (A038446). - Jeppe Stig Nielsen, May 18 2023 LINKS Jeppe Stig Nielsen, Table of n, a(n) for n = 1..10000 (terms 1..1000 from T. D. Noe) MAPLE 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 MATHEMATICA Flatten[Select[FromDigits/@Permutations[Join[{1, 1, 1, 1}, PadRight[{}, 7, 0]]], PrimeQ]] // Union (* Harvey P. Dale, May 09 2019 *) PROG (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 (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 CROSSREFS Cf. A038446. Cf. A020449, A062339, A235154. Sequence in context: A191244 A269066 A161786 * A159863 A234180 A054037 Adjacent sequences: A157708 A157709 A157710 * A157712 A157713 A157714 KEYWORD nonn,base AUTHOR Lekraj Beedassy, Mar 04 2009 EXTENSIONS Extended by numerous authors, Mar 06 2009 STATUS approved

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Last modified August 15 03:46 EDT 2024. Contains 375172 sequences. (Running on oeis4.)