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%I #26 Nov 05 2017 14:10:38
%S 1,7,21,31,73,93,107,127,273,313,341,381,403,443,471,511,1057,1137,
%T 1193,1273,1317,1397,1453,1533,1571,1651,1707,1787,1831,1911,1967,
%U 2047,4161,4321,4433,4593,4681,4841,4953,5113,5189,5349,5461,5621,5709,5869,5981,6141,6211,6371,6483,6643,6731,6891,7003,7163,7239
%N a(0) = 1; for n>0, working in binary, write n followed by 1 then n-reversed (including leading zeros); show result in base 10.
%C a(n) = A062383(n) + A264618(n); n>0: A070939(a(n)) = 2*A070939(n)+1; A000120(a(n)) = 2*A000120(n)+1; n>0: A023416(a(n)) = 2*A023416(n). - _Reinhard Zumkeller_, Dec 01 2015
%H N. J. A. Sloane, <a href="/A264619/b264619.txt">Table of n, a(n) for n = 0..32767</a>
%e 1 -> 111 = 7,
%e 10 -> 10101 = 21,
%e 11 -> 11111 = 31,
%e 100 -> 1001001 = 73,
%e ...
%t A264619[0] = 1; A264619[n_] := FromDigits[Join[#, {1}, Reverse[#]], 2]&@ IntegerDigits[n, 2] (* _JungHwan Min_, Dec 01 2015 *)
%t bnr[n_]:=Module[{idn2=IntegerDigits[n,2]},FromDigits[Join[idn2,{1}, Reverse[ idn2]],2]]; Join[{1},Array[bnr,60]] (* _Harvey P. Dale_, Nov 05 2017 *)
%o (Haskell)
%o a264619 0 = 1
%o a264619 n = foldr (\b v -> 2 * v + b) 0 $ (reverse bs ++ (1 : bs))
%o where bs = map fromIntegral $ a030308_row n
%o -- _Reinhard Zumkeller_, Dec 01 2015
%Y Cf. A006995, A048701 (n followed by n-reversed), A264618.
%Y First differences: A265029.
%Y Cf. A007088, A030308, A000120, A023416, A062383, A070939.
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Nov 30 2015
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