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%I #7 Jul 08 2016 09:40:34
%S 9399153082499072,20164508489351168,21992587709382656,
%T 25039386409435136,25537472011436031,26756191491457023,
%U 45443223518445567,47474422651813887,59772891590033408,64241529683443712,73381925783601152
%N Numbers n such that n and n+1 both have 38 divisors.
%H Charles R Greathouse IV, <a href="/A274810/b274810.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) is(n)=numdiv(n)==38 && numdiv(n+1)==38
%o (PARI) has(n)=if(n%4==2, ispower(n/2, 18, &n) && isprime(n), bitand(n, 524287)==262144 && isprime(n>>18) && n>262144) \\ check if n is even with 38 divisors
%o list(lim)=my(v=List(), t); forprime(p=2, sqrtnint(lim\=1, 37), t=p^37; if(has(t+1), listput(v, t)); if(has(t-1), listput(v, t-1))); forprime(p=3, sqrtnint(lim\3, 18), my(p18=p^18); forprime(q=3, lim\p18, if(p==q, next); t=p18*q; if(has(t+1), listput(v, t)); if(has(t-1), listput(v, t-1)))); Set(v)
%Y Intersection of A005237 and A175747.
%K nonn
%O 1,1
%A _Charles R Greathouse IV_, Jul 08 2016
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