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%I #15 Dec 30 2020 04:12:10
%S 0,0,1,0,1,1,1,1,0,1,2,1,1,1,2,1,1,1,2,2,1,0,2,1,1,2,2,1,1,2,1,1,2,2,
%T 1,1,2,3,1,1,2,2,2,2,2,1,1,2,3,1,1,2,2,0,2,2,2,1,1,2,3,1,1,2,2,1,2,2,
%U 3,2,1,3,2,1,2,3,2,1,2,1,2,2,1,2,2,3,2,1
%N Number of exponents >= 2 in canonical prime factorization of A025487(n) (first integer of each prime signature).
%C Length of row n of A212175 equals a(n) if a(n) is positive, 1 otherwise.
%H Amiram Eldar, <a href="/A212178/b212178.txt">Table of n, a(n) for n = 1..10000</a>
%H Will Nicholes, <a href="http://willnicholes.com/math/primesiglist.htm">Prime Signatures</a>
%H <a href="/index/Pri#prime_signature">Index entries for sequences related to prime signature</a>
%F a(n) = A056170(A025487(n)).
%e The canonical prime factorization of 24 (2^3*3) has 1 exponent that equals or exceeds 2. Since 24 = A025487(8), a(8) = 1.
%Y Cf. A025487, A212172.
%K nonn
%O 1,11
%A _Matthew Vandermast_, Jun 04 2012