%I A117711
%S A117711 0,1,5,6501,8400,10542,10795,18760,21540,32340,45850,50142,50692,55200,
%T A117711 60501,72490,91390,104412,127750,160230,170185,179401,208507,239800,
%U A117711 250717,272001,273208,333940,346801,400675,429070,442002,520087,536107
%N A117711 Pentagonal numbers for which both the sum of the digits and the product
of the digits are pentagonal numbers.
%e A117711 6501 is in the sequence because it is a pentagonal number and (1) the
sum of its digits 6+5+0+1=12 is a pentagonal number and (2)the product
of its digits 6*5*0*1=0 is also a pentagonal number.
%Y A117711 Cf. A000326.
%Y A117711 Sequence in context: A072021 A079812 A137694 this_sequence A116140 A145530
A067816
%Y A117711 Adjacent sequences: A117708 A117709 A117710 this_sequence A117712 A117713
A117714
%K A117711 base,nonn
%O A117711 0,3
%A A117711 Luc Stevens (lms022(AT)yahoo.com), Apr 13 2006
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