OFFSET

1,1

COMMENTS

Also numbers k such that k concatenated with k-1 gives the product of two numbers which differ by 5.

Also numbers k such that k concatenated with k+3 gives the product of two numbers which differ by 3.

Also numbers k such that k concatenated with k+5 gives the product of two numbers which differ by 1.

EXAMPLE

62918301//62918300 = 79321055 * 79321060, where // denotes concatenation.

62918301//62918304 = 79321056 * 79321059.

62918301//62918306 = 79321057 * 79321058.

CROSSREFS

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, Feb 06 2006

EXTENSIONS

Edited by N. J. A. Sloane, Apr 15 2007

STATUS

approved