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A100817 Product of the digits of n, each doubled. 1
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, 48, 56, 64, 72, 0, 12, 24, 36, 48, 60, 72, 84, 96, 108, 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 0, 20, 40, 60, 80, 100, 120, 140, 160, 180, 0, 24, 48, 72, 96, 120, 144, 168 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..67.

FORMULA

a(n) = A007954(n) *2^A055642(n). - R. J. Mathar, Oct 02 2019

EXAMPLE

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

MAPLE

A100817 := proc(n::integer)

    if n = 0 then

        0;

    else

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

    end if;

end proc:

seq(A100817(n), n=0..100) ; # R. J. Mathar, Oct 02 2019

MATHEMATICA

Times@@(2*IntegerDigits[#])&/@Range[0, 70] (* Harvey P. Dale, Jan 16 2012 *)

PROG

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

CROSSREFS

Cf. A007954.

Sequence in context: A271907 A069816 A088116 * A074157 A076309 A088133

Adjacent sequences:  A100814 A100815 A100816 * A100818 A100819 A100820

KEYWORD

nonn,base,easy

AUTHOR

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

STATUS

approved

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Last modified September 18 23:16 EDT 2021. Contains 347548 sequences. (Running on oeis4.)