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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.

Cf. A000005, A274357.

Sequence in context: A241245 A260105 A084804 * A025515 A031576 A204966

Adjacent sequences:  A274357 A274358 A274359 * A274361 A274362 A274363

KEYWORD

nonn

AUTHOR

Charles R Greathouse IV, Jun 19 2016

STATUS

approved

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Last modified May 25 03:39 EDT 2022. Contains 354047 sequences. (Running on oeis4.)