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%I #20 Nov 06 2017 02:46:14
%S 1,3,4,5,7,9,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,
%T 89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,
%U 179,181,191,193,197,199,211,223,227,229,233,239,241
%N Indices of record values in A001783.
%C Indices k such that A001783(k) is larger than all preceding terms of that sequence. The corresponding values A001783(k) are given in A193338.
%C It appears that, except for 1, 2, 4, and 9, this is all and only the primes. (It certainly includes all odd primes.) - _Franklin T. Adams-Watters_, Aug 11 2011
%C It appears that this is the sequence of indices of records in A206369. - _Michel Marcus_, Nov 04 2017
%H Michael De Vlieger, <a href="/A193339/b193339.txt">Table of n, a(n) for n = 1..10000</a>
%t Block[{s = Table[Times @@ Select[Range@ n, CoprimeQ[n, #] &], {n, 250}], t}, t = Union@ FoldList[Max, s]; Map[FirstPosition[s, #][[1]] &, t]] (* or *)
%t Union[Prime@ Range[2, 53], Range[3]^2] (* _Michael De Vlieger_, Nov 04 2017 *)
%o (PARI) m=0;for(n=1,599,m+0<(m=max(m,A001783(n))) & print1(n", "))
%Y Cf. A067126.
%K nonn
%O 1,2
%A _M. F. Hasler_, Jul 23 2011
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