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A113623 Highly composite numbers containing only noncomposite digits (1,2,3,5,7). 1
1, 2, 3, 5, 7, 12, 15, 21, 25, 27, 32, 35, 72, 75, 112, 125, 135, 175, 225, 252, 315, 375, 512, 525, 735, 1125, 1152, 1215, 1225, 1323, 1372, 1512, 1575, 1715, 2352, 3125, 3375, 13122, 13125, 15552, 25515, 25725, 31752, 35721, 55125, 77175, 111132 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..47.

EXAMPLE

175 is a term since 175 = 5^2*7 and contains digits 1,5,7 none of which is composite. 175 is a member of A002473.

MAPLE

isA002473 := proc(n) local ifs ; if n <= 10 then true ; else ifs := ifactors(n)[2] ; if max( seq(op(1, i), i=ifs) ) <= 7 then true; else false ; fi ; fi ; end: isA113623 := proc(n) local digs ; if isA002473(n) then if convert(convert(n, base, 10), set) minus {1, 2, 3, 5, 7} <> {} then false ; else true ; fi ; else false ; fi ; end: for n from 1 to 150000 do if isA113623(n) then printf("%d, ", n) ; fi ; od; # R. J. Mathar, Aug 28 2007

CROSSREFS

Cf. A002473.

Sequence in context: A309370 A022438 A193760 * A308868 A078912 A105930

Adjacent sequences:  A113620 A113621 A113622 * A113624 A113625 A113626

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Nov 10 2005

EXTENSIONS

More terms from R. J. Mathar, Aug 28 2007

STATUS

approved

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Last modified September 24 15:14 EDT 2020. Contains 337321 sequences. (Running on oeis4.)