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%I #18 Jun 29 2018 12:02:17
%S 1,4,9,16,25,36,49,64,81,1,2,6,12,20,30,42,56,72,90,4,6,16,30,48,70,
%T 96,126,160,198,9,12,30,54,84,120,162,210,264,324,16,20,48,84,128,180,
%U 240,308,384,468,25,30,70,120,180,250,330,420,520,630,36,42,96,162,240,330
%N a(n) is the product of the sum and the product of the digits of n (0 is not to be considered a factor in the product).
%H Alois P. Heinz, <a href="/A062331/b062331.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Harry J. Smith)
%e a(49) = (4+9)*(4*9) = 13*36 = 458.
%p a:= n-> (l-> add(i, i=l)*mul(`if`(i=0, 1, i), i=l))(convert(n, base, 10)):
%p seq(a(n), n=1..100); # _Alois P. Heinz_, Jun 29 2018
%t psd[n_]:=Module[{idnx0=Select[IntegerDigits[n],#>0&]},Times@@idnx0 Total[idnx0]]
%t psd/@Range[90] (* _Harvey P. Dale_, Feb 24 2011 *)
%t Array[Times @@ DeleteCases[#, 0]*Total@ # &@ IntegerDigits[#] &, 65] (* _Michael De Vlieger_, Jun 29 2018 *)
%o (PARI) SumD(x)= { s=0; while (x>9, s+=x-10*(x\10); x\=10); return(s + x) } ProdNzD(x)= { p=1; while (x>9, d=x-10*(x\10); if (d, p*=d); x\=10); return(p*x) } { for (n=1, 1000, write("b062331.txt", n, " ", SumD(n)*ProdNzD(n)) ) } \\ _Harry J. Smith_, Aug 05 2009
%Y Cf. A007953, A051801.
%K nonn,easy,base
%O 1,2
%A _Amarnath Murthy_, Jun 21 2001
%E More terms from Larry Reeves (larryr(AT)acm.org), Jun 22 2001
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