A324701 Lexicographically earliest sequence containing 1 and all positive integers n such that the prime indices of n - 1 already belong to the sequence.

1, 3, 5, 6, 9, 11, 12, 14, 17, 21, 23, 24, 26, 27, 32, 33, 38, 41, 44, 45, 47, 51, 53, 56, 60, 63, 65, 66, 74, 75, 81, 84, 87, 89, 90, 93, 101, 102, 104, 105, 111, 116, 119, 122, 125, 126, 129, 131, 132, 138, 144, 147, 149, 156, 161, 164, 167, 170, 173, 177

Offset

1,2

Comments

A self-describing sequence, similar to A304360.

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.

Links

Table of n, a(n) for n=1..60.

Formula

a(n) = A324700(n) + 1.

Mathematica

aQ[n_]:=Switch[n, 0, False, 1, True, _, And@@Cases[FactorInteger[n-1], {p_, k_}:>aQ[PrimePi[p]]]];
Select[Range[0, 100], aQ]

Crossrefs

Prime indices of A324700.

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

Cf. A324694, A324695, A324696, A324697, A324698, A324699, A324702, A324703, A324704, A324705.

Sequence in context: A225005 A053091 A367499 * A047271 A047445 A341349

Adjacent sequences: A324698 A324699 A324700 * A324702 A324703 A324704

Keyword

nonn

Author

Gus Wiseman, Mar 10 2019

Status

approved