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A274360 Numbers n such that n and n+1 both have 18 divisors. 2
6075, 23275, 25856, 26900, 33524, 45324, 46475, 61299, 61347, 77076, 82075, 93924, 96236, 107775, 111924, 117324, 118700, 133524, 137924, 155771, 209524, 210176, 219275, 229275, 230643, 234099, 257724, 258475, 272924, 275300, 278271, 312987, 325899, 332667, 348524 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
PROG
(PARI) is(n)=numdiv(n)==18 && numdiv(n+1)==18
(PARI) list(lim)=my(v=List()); forprime(p=2, sqrtint(lim\12), forprime(q=2, sqrtint(lim\p^2\2), if(p==q, next); my(pq2=(p*q)^2); forprime(r=2, lim\pq2, if(p==r || q==r, next); t=pq2*r; if(numdiv(t-1)==18, listput(v, t-1)); if(numdiv(t+1)==18, listput(v, t))))); Set(v)
CROSSREFS
Intersection of A005237 and A030636.
Sequence in context: A241245 A260105 A084804 * A025515 A031576 A204966
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified March 19 06:32 EDT 2024. Contains 370953 sequences. (Running on oeis4.)