A116279 Numbers k such that k*(k+2) gives the concatenation of two numbers m and m-1.

36363636363, 45454545454, 54545454545, 63636363636, 72727272727, 81818181818, 90909090909, 428571428571428571428, 571428571428571428571, 714285714285714285714, 857142857142857142857

Offset

1,1

Links

Table of n, a(n) for n=1..11.

Example

36363636363 * 36363636365 = 13223140496//13223140495, where // denotes concatenation.

Crossrefs

Cf. A102567, A116273, A116280, A116286.

Sequence in context: A022262 A233849 A370486 * A369689 A106497 A204097

Adjacent sequences: A116276 A116277 A116278 * A116280 A116281 A116282

Keyword

nonn,base

Author

Giovanni Resta, Feb 06 2006

Status

approved