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%I #9 Mar 27 2024 09:15:47
%S 0,1,7337,12692,19505,37505,61337,75440,146432,240752,326801,358400,
%T 620417,708401,802217,851312,1007345,1062272,1176500,1235801,1422452,
%U 1622225,1835120,1909001,2061137,2219105,2300276,2728001,4010672,4803401,5043017,5165012,7026032,7315220,7462001
%N Icosagonal numbers for which the sum of the digits is also an icosagonal number.
%e 7337 is in the sequence because (1) it is an icosagonal number and (2) the sum of the digits 7+3+3+7=20 is also an icosagonal number.
%o (PARI) isok(n) = ispolygonal(n, 20) && ispolygonal(sumdigits(n), 20); \\ _Michel Marcus_, Feb 27 2014
%Y Cf. A007953, A051872.
%K nonn,base
%O 1,3
%A Luc Stevens (lms022(AT)yahoo.com), Apr 29 2006
%E a(11) corrected by _Georg Fischer_, Mar 27 2024
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