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%I #36 Mar 27 2023 03:38:07
%S 198,288,378,396,468,486,558,576,594,648,666,684,738,756,774,792,828,
%T 846,864,882,918,936,954,972,990,1098,1188,1278,1296,1368,1386,1458,
%U 1476,1494,1548,1566,1584,1638,1656,1674,1692,1728,1746,1764,1782,1818,1836,1854
%N Harshad numbers with sum of digits equal to 18.
%C Even numbers with sum of digits equal to 18 are Harshad numbers (A005349).
%C If k is a term, then so is 10*k. - _Robert Israel_, Mar 26 2023
%H Robert Israel, <a href="/A334403/b334403.txt">Table of n, a(n) for n = 1..10000</a>
%e 198/18 = 11.
%p filter:= n -> convert(convert(n,base,10),`+`) = 18:
%p select(filter, [seq(i,i=18...4000, 18)]); # _Robert Israel_, Mar 26 2023
%t Select[18 * Range[100], Plus @@ IntegerDigits[#] == 18 &] (* _Amiram Eldar_, Sep 08 2020 *)
%o (PARI) isok(m) = my(s=sumdigits(m)); (s==18) && !(m%s); \\ _Michel Marcus_, Sep 08 2020
%o (PARI) first(n) = {my(res = vector(n), t = 0); forstep(i = 18, oo, 18, if(vecsum(digits(i)) == 18, t++; res[t] = i; if(t >= n, return(res) ) ) ) } \\ _David A. Corneth_, Sep 08 2020
%Y Intersection of A005349 and A235228.
%Y Subsequence of A008600.
%Y Cf. A002998.
%K nonn,easy,base
%O 1,1
%A _Davide Rotondo_, Sep 08 2020
%E More terms from _Michel Marcus_, Sep 08 2020
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