A116314 Numbers k such that k*(k+1) gives the concatenation of two numbers m and m+4.

28, 72, 79822845, 69852478553064869297984899963807, 77473062193002372448027740546439, 77747359197583788609974143907619, 84341826458653210947638195982115, 85367942837521291760016984490251

Offset: 1

Author

Giovanni Resta, Feb 06 2006

Keywords

• nonn
• base

Examples

			79822845 * 79822846 = 63716866//63716870, where // denotes concatenation.
		

Crossrefs

Cf. A116171, A116307, A116315, A116322.