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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.

A371170 Positive integers with at most as many prime factors (A001222) as distinct divisors of prime indices (A370820).

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%I A371170 #8 Mar 18 2024 11:45:31
%S A371170 1,2,3,5,6,7,9,10,11,13,14,15,17,19,21,22,23,25,26,28,29,30,31,33,34,
%T A371170 35,37,38,39,41,42,43,45,46,47,49,51,52,53,55,57,58,59,61,62,63,65,66,
%U A371170 67,69,70,71,73,74,75,76,77,78,79,82,83,85,86,87,89,91,92
%N A371170 Positive integers with at most as many prime factors (A001222) as distinct divisors of prime indices (A370820).
%C A371170 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.
%e A371170 The prime indices of 105 are {2,3,4}, and there are 3 prime factors (3,5,7) and 4 distinct divisors of prime indices (1,2,3,4), so 105 is in the sequence.
%e A371170 The terms together with their prime indices begin:
%e A371170      1: {}       22: {1,5}      42: {1,2,4}    63: {2,2,4}
%e A371170      2: {1}      23: {9}        43: {14}       65: {3,6}
%e A371170      3: {2}      25: {3,3}      45: {2,2,3}    66: {1,2,5}
%e A371170      5: {3}      26: {1,6}      46: {1,9}      67: {19}
%e A371170      6: {1,2}    28: {1,1,4}    47: {15}       69: {2,9}
%e A371170      7: {4}      29: {10}       49: {4,4}      70: {1,3,4}
%e A371170      9: {2,2}    30: {1,2,3}    51: {2,7}      71: {20}
%e A371170     10: {1,3}    31: {11}       52: {1,1,6}    73: {21}
%e A371170     11: {5}      33: {2,5}      53: {16}       74: {1,12}
%e A371170     13: {6}      34: {1,7}      55: {3,5}      75: {2,3,3}
%e A371170     14: {1,4}    35: {3,4}      57: {2,8}      76: {1,1,8}
%e A371170     15: {2,3}    37: {12}       58: {1,10}     77: {4,5}
%e A371170     17: {7}      38: {1,8}      59: {17}       78: {1,2,6}
%e A371170     19: {8}      39: {2,6}      61: {18}       79: {22}
%e A371170     21: {2,4}    41: {13}       62: {1,11}     82: {1,13}
%t A371170 Select[Range[100],PrimeOmega[#]<=Length[Union @@ Divisors/@PrimePi/@First/@If[#==1,{},FactorInteger[#]]]&]
%Y A371170 The complement is A370348, counted by A371171.
%Y A371170 The case of equality is A370802, counted by A371130, strict A371128.
%Y A371170 The RHS is A370820, for prime factors instead of divisors A303975.
%Y A371170 The strict version is A371168 counted by A371173.
%Y A371170 The opposite version is A371169.
%Y A371170 Choosable partitions: A239312 (A368110), A355740 (A370320), A370592 (A368100), A370593 (A355529).
%Y A371170 A000005 counts divisors.
%Y A371170 A001221 counts distinct prime factors.
%Y A371170 A027746 lists prime factors, indices A112798, length A001222.
%Y A371170 A355731 counts choices of a divisor of each prime index, firsts A355732.
%Y A371170 Cf. A003963, A319899, A355737, A355739, A355741, A370808, A371127.
%K A371170 nonn
%O A371170 1,2
%A A371170 _Gus Wiseman_, Mar 16 2024