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A106419 Smallest number beginning with 9 that is the product of exactly n distinct primes. 28
97, 91, 902, 910, 9030, 91770, 903210, 9699690, 900029130, 9146807670, 902340208770, 9426343036110, 900781858106130, 90004386781078770, 914836017997511610, 90100977291211496610, 9000008798605567472730 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..17.

EXAMPLE

a(2) = 91 = 7*13.

PROG

(PARI) a(n) = {i = prod(i=1, n, prime(i)); while ((digits(i)[1] != 9) || (omega(i) != n) || (bigomega(i) != n), i++); i; } \\ Michel Marcus, Sep 14 2013

CROSSREFS

Cf. A077326-A077334, A106411-A106419, A106421-A106429.

Sequence in context: A075478 A126146 A112667 * A253387 A074482 A130765

Adjacent sequences:  A106416 A106417 A106418 * A106420 A106421 A106422

KEYWORD

base,nonn

AUTHOR

Ray Chandler, May 02 2005

STATUS

approved

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Last modified March 29 13:11 EDT 2017. Contains 284270 sequences.