OFFSET
1,2
COMMENTS
PROG
(PARI)
allocatemem(2^30);
default(parisizemax, 2^31);
up_to = (2^25)+2;
A061395(n) = if(1==n, 0, primepi(vecmax(factor(n)[, 1])));
m_inverses = Map();
q2 = 0; prev=1; for(n=1, up_to, found_it = 0; fordiv(prev, d, if(!mapisdefined(m_inverses, (prev/d)), found_it = (prev/d); mapput(m_inverses, (prev/d), n); break)); if(!found_it, apu = prev; while(mapisdefined(m_inverses, try = prev*A053669(apu)), apu *= A053669(apu)); found_it = try; mapput(m_inverses, try, n)); if((q1=A061395(found_it)) != q2, write("b302774.txt", q1, " ", n-1); write("b302775.txt", q1, " ", found_it)); prev = found_it; q2 = q1);
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 04 2018
STATUS
approved