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A230041 Primes related to the strictly increasing subsequence of A053666. 6
2, 3, 5, 7, 19, 29, 37, 47, 59, 79, 89, 199, 269, 359, 379, 389, 479, 499, 599, 797, 887, 997, 1889, 1999, 2689, 2699, 2789, 2999, 3889, 3989, 4789, 4799, 4889, 4999, 6899, 8999, 25999, 27799, 28789, 28979, 29989, 37799, 37889, 39799, 39989, 48799, 48889 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(1)=2; a(n+1) is the smallest prime with product of digits > product of digits of a(n).

From Wolfdieter Lang, Oct 31 2014 (Start)

A053666 is sieved as follows:

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, ...

2, 3, 5, 7, 1, 3, 7, 9, 6, 18,  3, 21,  4, 12, 28, ...

2, 3, 5, 7, x, x, x, 9, x, 18,  x, 21,  x,  x, 28,

and the related primes are:

2, 3, 5, 7,         19,    29,     37,         47, ...

(End)

------------------------------------------------------

LINKS

Shyam Sunder Gupta, Table of n, a(n) for n = 1..142

EXAMPLE

a(6) = 29, product of digits is 18; a(7) = 37, product of digits is 21 and 21 > 18.

MATHEMATICA

a = {}; t = 0; Do[s = Apply[Times, IntegerDigits[Prime[n]]]; If[s > t, t = s; AppendTo[a, Prime[n]]], {n, 1, 10^4}]; a

CROSSREFS

Cf. A000040, A069802, A053666.

Sequence in context: A025019 A140327 A163074 * A068803 A184902 A048419

Adjacent sequences:  A230038 A230039 A230040 * A230042 A230043 A230044

KEYWORD

nonn,base,easy

AUTHOR

Shyam Sunder Gupta, Oct 06 2013

EXTENSIONS

Edited. Name specified. A000040, A053666 and 'easy' added. - Wolfdieter Lang, Oct 31 2014

STATUS

approved

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Last modified May 7 16:00 EDT 2021. Contains 343652 sequences. (Running on oeis4.)