OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000

EXAMPLE

128 is a member as 1*2*8 = 16 is a square. 140 is also a member as 1*4 = 4.

PROG

(PARI) ok(k)={my(d=digits(k)); issquare(prod(i=1, #d, if(d[i], d[i], 1)))} \\ Andrew Howroyd, Sep 17 2024

CROSSREFS

KEYWORD

nonn,base,easy

AUTHOR

Amarnath Murthy, Jun 26 2001

EXTENSIONS

Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jul 06 2001

Offset changed by Andrew Howroyd, Sep 17 2024

STATUS

approved