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A139182
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Numbers n such that pi(n)=d_1!!*d_2!!*...*d_k!! where d_1 d_2 ... d_k is the decimal expansion of n.
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1
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50, 51, 125, 15405, 26205, 226700, 226701, 226710, 226711, 513090, 513091, 1351832, 8210065
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Numbers n with a product of the double-factorials of the digits equal to A000720(n).
If n is in the sequence, 10 divides n and n+1 is composite then n+1 is in the sequence. [This sentence seems to be missing some words and the first part appears to be wrong, as 51 is in the sequence and 10 does not divide 51. - R. J. Mathar, Jan 22 2011]
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EXAMPLE
| pi(8210065)=8!!*2!!*1!!*0!!*0!!*6!!*5!!.
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CROSSREFS
| Cf. A066457, A006882.
Sequence in context: A078289 A043618 A134691 * A081646 A052261 A118146
Adjacent sequences: A139179 A139180 A139181 * A139183 A139184 A139185
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KEYWORD
| base,nonn,less,more
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), Apr 19 2008
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