OFFSET
1,1
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..100
EXAMPLE
a(4) = 42 hence a(5) = (4 + 2) * (4*2) = 6*8 = 48.
PROG
(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
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Amarnath Murthy, Jun 21 2001
EXTENSIONS
Corrected and extended by Larry Reeves (larryr(AT)acm.org) and Harvey P. Dale, Jun 22 2001
STATUS
approved