%I #13 Jan 01 2020 19:00:08
%S 1,1,3,5,5,7,9,11,13,13,15,17,19,21,23,25,25,27,29,31,33,35,37,39,41,
%T 41,43,45,47,49,51,53,55,57,59,61,61,63,65,67,69,71,73,75,77,79,81,83,
%U 85,85,87,89,91,93,95,97,99,101,103,105,107,109,111,113,113,115,117,119,121,123,125,127,129,131,133,135,137,139,141,143,145,145,147,149,151,153,155,157,159,161,163,165,167,169,171,173,175,177,179,181
%N A P_4-stuttered arithmetic progression with a(n+1)=a(n) if n is square, a(n+1)=a(n)+2 otherwise.
%C P_4(i) = the i-th square.
%H Harvey P. Dale, <a href="/A122800/b122800.txt">Table of n, a(n) for n = 1..1000</a>
%H Grady D. Bullington, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL10/Bullington/bullington7.html">The Connell Sum Sequence</a>, J. Integer Seq. 10 (2007), Article 07.2.6. (includes direct formula for a(n))
%H Douglas E. Iannucci and Donna Mills-Taylor, <a href="http://www.cs.uwaterloo.ca/journals/JIS/IANN/iann1.html">On Generalizing the Connell Sequence</a>, J. Integer Sequences, Vol. 2, 1999, #99.1.7.
%F a(n) = A045928(n)-n+1.
%t nxt[{n_,a_}]:={n+1,If[IntegerQ[Sqrt[n+1]],a,a+2]}; NestList[nxt,{0,1},100][[All,2]] (* _Harvey P. Dale_, Jan 01 2020 *)
%o (PARI) lista(m) = {aa = 1; for (i=1, m, print1(aa, ", "); if (! issquare(i), aa = aa + 2););} \\ _Michel Marcus_, Apr 01 2013
%Y Cf. A001614, A122793, A122794, A122795, A122796, A122797, A122798, A122799.
%K nonn,easy
%O 1,3
%A Grady Bullington (bullingt(AT)uwosh.edu), Sep 14 2006
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