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A062330 a(n) = product of the sum and product of the digits of a(n-1) (0 is not to be considered a factor in the product). 1

%I

%S 2,4,16,42,48,384,1440,144,144,144,144,144,144,144,144,144,144,144,

%T 144,144,144,144,144,144,144,144,144,144,144,144,144,144,144,144,144,

%U 144,144,144,144,144,144,144,144,144,144,144,144,144,144,144,144,144,144

%N a(n) = product of the sum and product of the digits of a(n-1) (0 is not to be considered a factor in the product).

%H Harry J. Smith, <a href="/A062330/b062330.txt">Table of n, a(n) for n = 1..100</a>

%e a(4) = 42 hence a(5) = (4 + 2) * (4*2) = 6*8 = 48.

%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, 100, if (n>1, a=SumD(a)*ProdNzD(a), a=2); write("b062330.txt", n, " ", a) ) } \\ _Harry J. Smith_, Aug 05 2009

%K nonn,base,easy

%O 1,1

%A _Amarnath Murthy_, Jun 21 2001

%E Corrected and extended by Larry Reeves (larryr(AT)acm.org) and _Harvey P. Dale_, Jun 22 2001

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Last modified November 29 18:41 EST 2021. Contains 349416 sequences. (Running on oeis4.)