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Enneagonal numbers for which both the sum of the digits and the product of the digits are also enneagonal numbers.
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%I #5 Apr 13 2020 14:07:41

%S 0,1,9,1350,10071,39804,46806,66309,80484,175056,204369,226950,235950,

%T 260169,305916,450186,460284,473064,556206,570246,581604,676500,

%U 704481,733029,822075,835701,930606,1015476,1065084,1155750,1208634,1305096

%N Enneagonal numbers for which both the sum of the digits and the product of the digits are also enneagonal numbers.

%C An enneagopnal number is also called a nonagonal number. - _Harvey P. Dale_, Apr 13 2020

%H Harvey P. Dale, <a href="/A117053/b117053.txt">Table of n, a(n) for n = 0..1000</a>

%e 39804 is in the sequence because (1) it is an enneagonal number,(2)the sum of its digits 3+9+8+0+4=24 is an enneagonal number and (3)the product of its digits 3*9*8*0*4=0 is also an enneagonal number.

%t With[{nnn=Table[(n(7n-5))/2,{n,0,1000}]},Select[nnn,MemberQ[nnn,Total[ IntegerDigits[ #]]]&&MemberQ[nnn,Times@@IntegerDigits[#]]&]] (* _Harvey P. Dale_, Apr 13 2020 *)

%Y Cf. A001106.

%K base,nonn

%O 0,3

%A Luc Stevens (lms022(AT)yahoo.com), Apr 15 2006