

A072510


Numbers n with property that n = product of first k divisors of n for some k.


4



1, 2, 3, 5, 6, 7, 8, 10, 11, 13, 14, 15, 17, 19, 21, 22, 23, 24, 26, 27, 29, 30, 31, 33, 34, 35, 37, 38, 39, 40, 41, 43, 46, 47, 51, 53, 55, 56, 57, 58, 59, 61, 62, 64, 65, 67, 69, 70, 71, 73, 74, 77, 79, 82, 83, 85, 86, 87, 89, 91, 93, 94, 95, 97, 101, 103, 105, 106, 107
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OFFSET

1,2


COMMENTS

Contains all prime numbers, numbers with two different prime factors... First 37 terms are the same as that of A036537. 54 is member of A036537, but it is not member of this sequence. 64 is member of this sequence but not of A036537.  Vladimir Baltic, Aug 03 2002


LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..10000


EXAMPLE

8 is a member as 8 = 1*2*4. but 9 is not as the divisors of 9 are 1,3,9 and 9 is not a partial product.


MATHEMATICA

Select[Range[110], MemberQ[FoldList[Times, 1, Divisors[#]], #]&] (* Harvey P. Dale, Jan 01 2014 *)


PROG

(PARI) isok(n) = {d = divisors(n); pr = 1; for(k=1, #d, pr *= d[k]; if (pr == n, return(1)); ); } \\ Michel Marcus, May 19 2017


CROSSREFS

Sequence in context: A268335 A002035 A036537 * A084116 A137620 A028765
Adjacent sequences: A072507 A072508 A072509 * A072511 A072512 A072513


KEYWORD

nonn


AUTHOR

Amarnath Murthy, Jul 22 2002


EXTENSIONS

More terms from Vladimir Baltic, Aug 03 2002


STATUS

approved



