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%I #7 Nov 01 2016 10:10:16
%S 1,2,2,3,3,3,3,3,5,5,5,5,5,5,7,7,7,7,7,7,7,7,7,7,11,7,7,11,11,11,11,
%T 11,11,11,11,11,11,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,17,13,
%U 17,17,17,17,17,17,17,17,17,17,19,17,17,19,19,17,19,19,19,19,19,19,19,19,19,19,19,19,23,19,23,19
%N a(1) = 1, for n>=1 a(n) is the largest prime factor of A002182(n).
%C For n>=1, the largest prime factor of the n-th highly composite number.
%H Joerg Arndt, <a href="/A272605/b272605.txt">Table of n, a(n) for n = 1..19999</a>
%e The first highly composite numbers with their prime factorizations:
%e n: A002182(n) = [factorization]
%e 1: 1 = []
%e 2: 2 = [2]
%e 3: 4 = [2^2]
%e 4: 6 = [2 * 3]
%e 5: 12 = [2^2 * 3]
%e 6: 24 = [2^3 * 3]
%e 7: 36 = [2^2 * 3^2]
%e 8: 48 = [2^4 * 3]
%e 9: 60 = [2^2 * 3 * 5]
%e 10: 120 = [2^3 * 3 * 5]
%e 11: 180 = [2^2 * 3^2 * 5]
%e 12: 240 = [2^4 * 3 * 5]
%e 13: 360 = [2^3 * 3^2 * 5]
%e 14: 720 = [2^4 * 3^2 * 5]
%e 15: 840 = [2^3 * 3 * 5 * 7]
%e 16: 1260 = [2^2 * 3^2 * 5 * 7]
%e 17: 1680 = [2^4 * 3 * 5 * 7]
%e 18: 2520 = [2^3 * 3^2 * 5 * 7]
%e 19: 5040 = [2^4 * 3^2 * 5 * 7]
%e 20: 7560 = [2^3 * 3^3 * 5 * 7]
%e 21: 10080 = [2^5 * 3^2 * 5 * 7]
%e 22: 15120 = [2^4 * 3^3 * 5 * 7]
%e 23: 20160 = [2^6 * 3^2 * 5 * 7]
%e 24: 25200 = [2^4 * 3^2 * 5^2 * 7]
%e 25: 27720 = [2^3 * 3^2 * 5 * 7 * 11]
%e 26: 45360 = [2^4 * 3^4 * 5 * 7]
%e 27: 50400 = [2^5 * 3^2 * 5^2 * 7]
%e 28: 55440 = [2^4 * 3^2 * 5 * 7 * 11]
%e 29: 83160 = [2^3 * 3^3 * 5 * 7 * 11]
%e 30: 110880 = [2^5 * 3^2 * 5 * 7 * 11]
%K nonn
%O 1,2
%A _Joerg Arndt_, Nov 01 2016