help needed in distinguishing two sequences

N. J. A. Sloane njas at research.att.com
Mon Dec 4 23:04:47 CET 2006


Dear Seqfans:  At present I have these two entries:
%I A055039
%S A055039 14,30,46,56,62,78,94,110,120,126,142,158,174,184,190,206,222,224,
%T A055039 238,248,254,270,286,302,312,318,334,350,366,376,382,398,414,430,
%U A055039 440,446,462,478,480,494,504,510,526,542,558,568,574,590,606,622
%N A055039 Numbers of the form 2^(2i+1)*(8*j+7).
%C A055039 The numbers not of the form x^2+y^2+2z^2.
%C A055039 These are the numbers not occurring as norms in the face-centered cubic lattice (cf. A004015).
%C A055039 Numbers of the form (16x^2+14)y^2. Also numbers of the form 6x^2 + 8x^2(2y -1). (Steve Waterman).
...
%Y A055039 Equals twice A004215. Not the same as A044075.
...

and

%I A044075
%S A044075 14,30,46,56,62,78,94,110,120,126,142,158,174,184,190,206,222,
%T A044075 224,248,254,270,286,302,312,318,334,350,366,376,382,398,414,
%U A044075 430,440,446,462,478,480,504,510,526,542,558,568,574,590,606
%N A044075 Numbers n such that the string 3,2 occurs in the base 4 representation of n but not of n-1.
%C A044075 Not the same as A055039.
...

It appears that the first properly contains the second,
the numbers 238, 494, ... being in the first but not the second.

I will start a new entry, A124169, with 238,494,...
Could someone compute further terms (and double-check everything)?

Thanks

Neil






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