A115429 Numbers k such that the concatenation of k with k+8 gives a square.

6001, 6433, 11085116, 44496481, 96040393, 115916930617, 227007035017, 274101929528, 434985419768, 749978863753, 996004003993, 1365379857457948, 1410590590957816, 1762388551055953, 2307340946901148, 2700383162251217

Offset: 1

Author

Giovanni Resta, Jan 24 2006

Keywords

• base
• nonn

Comments

Also numbers k such that k concatenated with k+7 gives the product of two numbers which differ by 2.

Also numbers k such that k concatenated with k+4 gives the product of two numbers which differ by 4.

Also numbers k such that k concatenated with k-1 gives the product of two numbers which differ by 6.

Also numbers k such that k concatenated with k-8 gives the product of two numbers which differ by 8.

Examples

			6001//6009 = 7747^2, where // denotes concatenation.
96040393//96040400 = 98000200 * 98000202.
96040393//96040397 = 98000199 * 98000203.
96040393//96040392 = 98000198 * 98000204.
		

Crossrefs

Cf. A030465, A102567, A115426, A115437, A115428, A115430, A115431, A115432, A115433, A115434, A115435, A115436, A115440.

Cf. A116107, A116109, A116113, A116239.

Cf. A116205, A115430, A116335, A116185, A116187, A116317.

Cf. A116131, A116112, A116152, A116159, A116282.

Extensions

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