OFFSET
1,1
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..1000
P. A. Loomis, An Interesting Family of Iterated Sequences
P. A. Loomis, An Introduction to Digit Product Sequences, J. Rec. Math., 32 (2003-2004), 147-151.
P. A. Loomis, An Introduction to Digit Product Sequences, J. Rec. Math., 32 (2003-2004), 147-151. [Annotated archived copy]
FORMULA
a(n) = n + A051801(n). - Reinhard Zumkeller, Jan 15 2012
EXAMPLE
a(59) = 59 + 5*9 = 104. a(66) = 66 + 6*6 = 102.
MATHEMATICA
Table[i+Times@@(IntegerDigits[i]/. 0->1), {i, 70}]
PROG
(ARIBAS): var stk: stack; end; for n := 1 to 80 do s := itoa(n); for j := 0 to length(s) -1 do k := atoi(s[j..j]); if k > 0 then stack_push(stk, k); end; end; write(n + product(stack2array(stk)), " "); end;
(PARI)
ProdNzD(x)= local(d, p); p=1; while (x>9, d=x-10*(x\10); if (d, p*=d); x\=10); return(p*x)
for (n=1, 1000, write("b063114.txt", n, " ", n + ProdNzD(n)) ) \\ Harry J. Smith, Aug 19 2009
(Haskell)
a063114 n = n + a051801 n -- Reinhard Zumkeller, Jan 15 2012
CROSSREFS
KEYWORD
AUTHOR
N. J. A. Sloane, Aug 08 2001
EXTENSIONS
More terms from Robert G. Wilson v and Klaus Brockhaus, Aug 09 2001
STATUS
approved