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%I #11 Aug 10 2024 15:26:45
%S 22,33,44,55,66,77,88,99,110,202,220,303,312,321,330,404,413,422,440,
%T 505,514,532,550,606,615,624,633,642,651,660,707,716,725,734,752,770,
%U 808,817,826,835,844,862,871,880,909,918,927,936,945,954,963,972,981
%N Composite numbers whose first digit is equal to the sum of all the other digits.
%H Harvey P. Dale, <a href="/A157529/b157529.txt">Table of n, a(n) for n = 1..1000</a>
%e 990 is a composite number whose first digit is equal to the sum of all the other digits.
%p a := proc (n) local nn: nn := convert(n, base, 10): if isprime(n) = false and nn[nops(nn)] = add(nn[j], j = 1 .. nops(nn)-1) then n else end if end proc: seq(a(n), n = 2 .. 1100); # _Emeric Deutsch_, Mar 07 2009
%t cnfdQ[n_]:=With[{id=IntegerDigits[n]},CompositeQ[n]&&id[[1]]==Total[Rest[id]]]; Select[ Range[1000],cnfdQ] (* _Harvey P. Dale_, Aug 10 2024 *)
%Y Cf. A002808.
%K base,nonn
%O 1,1
%A _Parthasarathy Nambi_, Mar 02 2009
%E Corrected and extended by _Emeric Deutsch_, Mar 07 2009