

A115426


Numbers k such that the concatenation of k with k+2 gives a square.


24



7874, 8119, 69476962, 98010199, 108746354942, 449212110367, 544978035127, 870501316279, 998001001999, 1428394731903223, 1499870932756487, 1806498025502498, 1830668275445687, 1911470478658759, 2255786189655202
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OFFSET

1,1


COMMENTS

Numbers k such that k concatenated with k+1 gives the product of two numbers which differ by 2.
Numbers k such that k concatenated with k2 gives the product of two numbers which differ by 4.
Numbers k such that k concatenated with k7 gives the product of two numbers which differ by 6.


LINKS



EXAMPLE

8119//8121 = 9011^2, where // denotes concatenation.
98010199//98010200 = 99000100 * 99000102.
98010199//98010197 = 99000099 * 99000103.


CROSSREFS

Cf. A030465, A102567, A115427, A115428, A115429, A115430, A115431, A115432, A115433, A115434, A115435, A115436, A115437.


KEYWORD

base,nonn


AUTHOR



EXTENSIONS



STATUS

approved



