A116205 - OEIS

%I #12 Jul 19 2021 01:56:07

%S 1,81,1353,3997,7723,23761,26271,76771,1415683,3890571,8495497,

%T 1066870443,1239366513,4198438981,4534273891,6502317141,6918679731,

%U 2199164200036329043,2820114781174460091,5500888421709400741

%N Numbers k such that k concatenated with k+7 gives the product of two numbers which differ by 3.

%C Also numbers k such that k concatenated with k+9 gives the product of two numbers which differ by 1.

%C Also numbers k such that k concatenated with k-3 gives the product of two numbers which differ by 7.

%Y Cf. A116179, A116172, A115429, A116173, A116193, A116336.

%Y Cf. A116132, A116099, A116139, A116152, A116269, A116348.

%K nonn,base

%O 1,2

%A _Giovanni Resta_, Feb 06 2006

%E Edited by _N. J. A. Sloane_, Apr 13 2007