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A117710 Pentagonal numbers for which the product of the digits is also a pentagonal number. 0

%I #2 Sep 29 2006 03:00:00

%S 0,1,5,51,70,210,330,590,715,1001,1080,1162,1520,1820,2035,2380,2501,

%T 3015,3290,3725,4030,4510,5017,5370,6112,6305,6501,6700,6902,7107,

%U 7740,8400,9087,9560,9801,10045,10292,10542,10795,11051,11310,11572,12105

%N Pentagonal numbers for which the product of the digits is also a pentagonal number.

%e 715 is in the sequence because it is a pentagonal number and the product of its digits 7*1*5=35 is also a pentagonal number.

%Y Cf. A000326.

%K base,nonn

%O 0,3

%A Luc Stevens (lms022(AT)yahoo.com), Apr 13 2006

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