Search: id:A143245 Results 1-1 of 1 results found. %I A143245 %S A143245 3,5,7,13,11,17,29,23,31,41,37,53,61,43,47,97,113,73,101,67,83,107,71, %T A143245 127,193,233,197,229,181,173,131,163,227,251,199,167,151,223,257,449, %U A143245 353,337,433,409,313,421,277,373,269,461,349,509,307,331,491,283,443 %N A143245 A098957 such that the number is prime: a(n)=If[PrimeQ[A098957(n)],A098957(n)]. %D A143245 Weisstein, Eric W. "Gray Code." http : // mathworld.wolfram.com/GrayCode.html %F A143245 a(n)=If[PrimeQ[A098957(n)],A098957(n)]. %t A143245 GrayCodeList[k_] := Module[{b = IntegerDigits[k, 2], i}, Do[ If[b[[i - 1]] == 1, b[[i]] = 1 - b[[i]]], {i, Length[b], 2, -1} ]; b ]; a[n_] = GrayCodeList[Prime[n]]; a0 = Table[Sum[a[n][[m + 1]]*2^m, {m, 0, Length[a[n]] - 1}], {n, 1, 200}]; Flatten[Table[If[PrimeQ[a0[[n]]], a0[[n]], {}], {n, 1, 200}]] %Y A143245 Cf. A098957. %Y A143245 Sequence in context: A161329 A111745 A098957 this_sequence A018205 A121047 A152075 %Y A143245 Adjacent sequences: A143242 A143243 A143244 this_sequence A143246 A143247 A143248 %K A143245 nonn,uned,probation %O A143245 1,1 %A A143245 Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Oct 21 2008 Search completed in 0.001 seconds