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%I #19 Jul 21 2015 03:01:43
%S 5,13,17,21,29,37,45,49,53,61,65,69,77,81,85,93,101,109,113,117,125,
%T 133,141,145,149,157,165,173,177,181,189,193,197,205,209,213,221,229,
%U 237,241,245,253,257,261,269,273,277,285,293,301,305,309,317,321,325
%N Odd numbers missing from A171947.
%C These are the odd terms in A171946.
%C Consider the sequence of first differences, divided by 4: 2, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, ... This is, almost certainly, A026465 without its leading 1. - _N. J. A. Sloane_, Oct 30 2014
%C This sequence appears to be the same as A260191, Numbers n such that there exists no square whose base-n digit sum is binomial(n,2), without that sequence's leading 3. - _Jon E. Schoenfield_, Jul 19 2015
%H Reinhard Zumkeller, <a href="/A249034/b249034.txt">Table of n, a(n) for n = 1..10000</a>
%t f[n_] := Block[{a = {1}, b = {}, k}, Do[k = 2; While[MemberQ[a, k] || MemberQ[b, k], k++]; AppendTo[a, 2 k - 1]; AppendTo[b, k], {i, 2, n}]; a]; Complement[Range[1, Max@ #, 2], #] &@ f@ 120 (* _Michael De Vlieger_, Jul 20 2015 *)
%o (Haskell)
%o a249034 n = a249034_list !! (n-1)
%o a249034_list = filter odd a171946_list
%o -- _Reinhard Zumkeller_, Oct 26 2014
%Y Cf. A026465, A171946, A171947, A260191.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Oct 26 2014
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