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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 11 04:29 EST 2018. Contains 318049 sequences. (Running on oeis4.)