A116169 Numbers k such that k concatenated with k+1 gives the product of two numbers which differ by 9.

9, 49, 1166975893986638437392162264780939, 1411174268292962563778302427727571, 1860631503683565562655236868895135

Offset: 1

Author

Giovanni Resta, Feb 06 2006

Keywords

• nonn
• base

Comments

Also numbers k such that k concatenated with k+9 gives the product of two numbers which differ by 7.

Examples

			49//50 = 66 * 75, where // denotes concatenation.
49//58 = 67 * 74.
		

Crossrefs

Cf. A116162, A116168, A116175, A116300.

Cf. A116215, A116174, A116223, A116353.

Extensions

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