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Even numbers that are not the sum or difference of two binary palindromes (A006995).
0

%I #9 Aug 08 2017 22:12:48

%S 9404,10120,13714,14576,15812,18622,35102,35438,38696,39164,39656,

%T 40072,40712,42776,43096,43256,43780,44560,45284,45796,46346,46532,

%U 46624,46858,46880,46984,47936,49622,50810,55048,56600,58564,60932,61190,62792,62986,67816,69244

%N Even numbers that are not the sum or difference of two binary palindromes (A006995).

%C Intersection of A261678 and A290393.

%t g[w_] := FromDigits[Join @@ w, 2]; bp[1]={1}; bp[n_] := Block[{b,r, h = Floor[n/2]}, Sort@ Flatten@ Table[b = IntegerDigits[k, 2, h]; r = Reverse@ b; If[OddQ@n, g /@ {{b, {0}, r}, {b, {1}, r}}, g@{b, r}], {k, 2^h/2, 2^h - 1}]]; pp = Sort@ Flatten[Table[bp[h], {h, 32}]]; T = Range[35000]*0; i = 0; While[i < Length[pp] - 1, i++; j = i + 1; While[j <= Length[pp] && (d = pp[[j]] - pp[[i]]) <= 70000, T[[d/2]] = 1; j++]]; pp = Select[pp, # <= 70000 &]; Select[2 Flatten[ Position[T, 0]], {} == Quiet@ IntegerPartitions[#, {2}, pp, 1] &] (* _Giovanni Resta_, Aug 08 2017 *)

%Y Cf. A006995, A241491, A261678, A290393.

%K nonn,base

%O 1,1

%A _Altug Alkan_, Jul 31 2017

%E a(7)-a(38) from _Giovanni Resta_, Aug 08 2017