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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A325266 Numbers whose adjusted frequency depth equals their number of prime factors counted with multiplicity.

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%I A325266 #6 Apr 17 2019 19:08:58
%S A325266 1,2,3,4,5,7,9,11,13,17,19,23,24,25,29,30,31,37,40,41,42,43,47,49,53,
%T A325266 54,56,59,61,66,67,70,71,73,78,79,83,88,89,97,101,102,103,104,105,107,
%U A325266 109,110,113,114,120,121,127,130,131,135,136,137,138,139,149
%N A325266 Numbers whose adjusted frequency depth equals their number of prime factors counted with multiplicity.
%C A325266 The adjusted frequency depth of a positive integer n is 0 if n = 1, and otherwise it is 1 plus the number of times one must apply A181819 to reach a prime number, where A181819(n = p^i*...*q^j) = prime(i)*...*prime(j) = product of primes indexed by the prime exponents of n. For example, 180 has adjusted frequency depth 5 because we have: 180 -> 18 -> 6 -> 4 -> 3.
%C A325266 The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k), so these are Heinz numbers of integer partitions whose adjusted frequency depth is equal to their length. The enumeration of these partitions by sum is given by A325246.
%e A325266 The sequence of terms together with their prime indices and their omega-sequences (see A323023) begins:
%e A325266    2:       {1} (1)
%e A325266    3:       {2} (1)
%e A325266    4:     {1,1} (2,1)
%e A325266    5:       {3} (1)
%e A325266    7:       {4} (1)
%e A325266    9:     {2,2} (2,1)
%e A325266   11:       {5} (1)
%e A325266   13:       {6} (1)
%e A325266   17:       {7} (1)
%e A325266   19:       {8} (1)
%e A325266   23:       {9} (1)
%e A325266   24: {1,1,1,2} (4,2,2,1)
%e A325266   25:     {3,3} (2,1)
%e A325266   29:      {10} (1)
%e A325266   30:   {1,2,3} (3,3,1)
%e A325266   31:      {11} (1)
%e A325266   37:      {12} (1)
%e A325266   40: {1,1,1,3} (4,2,2,1)
%e A325266   41:      {13} (1)
%e A325266   42:   {1,2,4} (3,3,1)
%t A325266 fdadj[n_Integer]:=If[n==1,0,Length[NestWhileList[Times@@Prime/@Last/@FactorInteger[#]&,n,!PrimeQ[#]&]]];
%t A325266 Select[Range[100],fdadj[#]==PrimeOmega[#]&]
%Y A325266 Cf. A056239, A112798, A118914, A181819, A225485, A323023, A325246, A325258, A325277, A325278, A325281, A325283.
%Y A325266 Omega-sequence statistics: A001222 (first omega), A001221 (second omega), A071625 (third omega), A323022 (fourth omega), A304465 (second-to-last omega), A182850 or A323014 (length/frequency depth), A325248 (Heinz number).
%K A325266 nonn
%O A325266 1,2
%A A325266 _Gus Wiseman_, Apr 17 2019