OFFSET
1,3
REFERENCES
Felice Russo, A set of new Smarandache Functions, Sequences and conjectures in number theory, pp-64, American Research Press, Lupton USA.
Amarnath Murthy, Exploring some new ideas on Smarandache Type Sets, Functions and sequences, Vol. 11, No. 1-2-3, Spring 2000.
Amarnath Murthy, On the infinitude of Smarandache multiplicative square sequence, (to be published in Smarandache Notions Journal).
FORMULA
a(n) ~ n^2. - Charles R Greathouse IV, Sep 19 2012
MATHEMATICA
Select[Range[0, 200]^2, IntegerQ[Sqrt[Times@@IntegerDigits[#]]]&] (* Harvey P. Dale, Oct 03 2014 *)
PROG
(PARI) isok(n) = {if (! issquare(n), return (0)); digs = digits(n, 10); issquare(prod(i=1, #digs, digs[i])); } \\ Michel Marcus, Aug 02 2013
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Larry Reeves (larryr(AT)acm.org), May 11 2001
STATUS
approved