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Product of the digits of n, each doubled.
1

%I #7 Oct 02 2019 06:02:40

%S 0,2,4,6,8,10,12,14,16,18,0,4,8,12,16,20,24,28,32,36,0,8,16,24,32,40,

%T 48,56,64,72,0,12,24,36,48,60,72,84,96,108,0,16,32,48,64,80,96,112,

%U 128,144,0,20,40,60,80,100,120,140,160,180,0,24,48,72,96,120,144,168

%N Product of the digits of n, each doubled.

%F a(n) = A007954(n) *2^A055642(n). - _R. J. Mathar_, Oct 02 2019

%e 10: (1+1)*(0+0)=0

%p A100817 := proc(n::integer)

%p if n = 0 then

%p 0;

%p else

%p mul( 2*d,d=convert(n,base,10)) ;

%p end if;

%p end proc:

%p seq(A100817(n),n=0..100) ; # _R. J. Mathar_, Oct 02 2019

%t Times@@(2*IntegerDigits[#])&/@Range[0,70] (* _Harvey P. Dale_, Jan 16 2012 *)

%o (Perl) #!/usr/local/bin/perl -w for $i (1..100){ @j = split "", $i; $prod=1; for (@j){ $prod *= $_ + $_; } print "$prod,"; }

%Y Cf. A007954.

%K nonn,base,easy

%O 0,2

%A gamo (gamo(AT)telecable.es), Jan 05 2005