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Lexicographically earliest sequence containing 3 and all positive integers n such that the prime indices of n - 1 already belong to the sequence.
12

%I #8 Mar 11 2019 20:48:53

%S 3,6,14,26,44,66,102,126,170,194,216,318,326,506,558,560,626,702,846,

%T 966,1014,1076,1182,1314,1322,1586,1626,1850,2112,2162,2198,2510,2526,

%U 2786,2796,3126,3506,3618,4050,4058,4122,4226,4344,4640,4826,5066,5298,5376

%N Lexicographically earliest sequence containing 3 and all positive integers n such that the prime indices of n - 1 already belong to the sequence.

%C A self-describing sequence, similar to A304360.

%C A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

%F a(n) = A324702(n) + 1.

%t aQ[n_]:=Switch[n,0,False,3,True,_,And@@Cases[FactorInteger[n-1],{p_,k_}:>aQ[PrimePi[p]]]];

%t Select[Range[0,1000],aQ]

%Y Prime indices of A324702.

%Y Cf. A000002, A000720, A001222, A001462, A007097, A045965, A055396, A061395, A064989, A079000, A079254, A109298, A112798, A276625, A277098, A304360.

%Y Cf. A324694, A324695, A324696, A324697, A324698, A324699, A324700, A324701, A324704, A324705.

%K nonn

%O 1,1

%A _Gus Wiseman_, Mar 11 2019