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%I #10 Jul 20 2021 23:47:06
%S 2,74,59264,510782,906902,81790664,92776472,10876856041862,
%T 11796926254874,18332259798794,18388650720624,32624670587648,
%U 32699883214248,43103618706398,44916698243804,66132258426302
%N Numbers k such that k concatenated with k+2 gives the product of two numbers which differ by 5.
%C Also numbers k such that k concatenated with k+6 gives the product of two numbers which differ by 3.
%C Also numbers k such that k concatenated with k+8 gives the product of two numbers which differ by 1.
%C If k+2 and k-4 have the same number of digits, then k is also in A116132 because k//k+2 = 10^d*k + k + 2 = m*(m+5) then implies k//k-4 = 10^d*k + k - 4 = m*(m+5) - 6 = (m-1)*(m+6). - _R. J. Mathar_, Aug 10 2008
%e 92776472//92776474 = 96320542 * 96320547, where // denotes concatenation.
%e 92776472//92776480 = 96320544 * 96320545.
%e 92776472//92776478 = 96320543 * 96320546.
%Y Cf. A116158, A116171, A116173, A116179, A116303.
%Y Cf. A116185, A115430, A116205, A116343, A116200, A116330.
%K nonn,base
%O 1,1
%A _Giovanni Resta_, Feb 06 2006
%E Edited by _N. J. A. Sloane_, Apr 15 2007
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