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Smallest number m such that the n-th prime is the median prime factor of 1..m, cf. A212300.
2

%I #5 Sep 01 2014 12:13:27

%S 1,7,21,43,79,119,185,249,333,431,535,655,773,907,1061,1213,1389,1563,

%T 1757,1959,2165,2399,2643,2897,3153,3425,3683,3987,4309,4631,4979,

%U 5287,5653,6009,6377,6749,7149,7539,7941,8359,8797,9227,9693,10159,10635,11117

%N Smallest number m such that the n-th prime is the median prime factor of 1..m, cf. A212300.

%C A212300(a(n)) = A000040(n).

%H Reinhard Zumkeller, <a href="/A246430/b246430.txt">Table of n, a(n) for n = 1..120</a>

%o (Haskell)

%o import Data.List (elemIndex); import Data.Maybe (fromJust)

%o a246430 = (+ 1) . fromJust . (`elemIndex` a212300_list) . a000040

%Y Cf. A212300, A000040.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Sep 01 2014