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%I #9 Jan 02 2023 12:30:48
%S 2,3,5,7,9,11,17,25,33,35,37,39,43,45,51,57,61,63,65,69,71,73,77,79,
%T 85,91,97,103,105,109,115,121,123,127,129,137,141,153,167,171,177,179,
%U 183,185,193,199,211,213,221,225,229,235,241,245,249,255,259,261
%N List of k such that A214686(k) = 1.
%C It seems that a(n) = 1 + floor(sqrt(A214686(a(n)+1)) which complies with an observation of Robert Israel.
%H Robert Israel, <a href="http://list.seqfan.eu/oldermail/seqfan/2012-July/009920.html">A214686</a>
%o (Sage)
%o def A214548_list(n) : # n is a search limit
%o a = []; r = 1; f = 1
%o for k in (1..n) :
%o f = f * k
%o if k-1 == gcd(r-1, f) :
%o a.append(k); t = 1
%o else :
%o for t in range(r-1, -1, -1) :
%o if gcd(t, f) == 1 : break
%o r = (k+1)*(r-t)
%o return a
%o A214548_list(261)
%K nonn
%O 1,1
%A _Peter Luschny_, Jul 28 2012
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