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 A116226 n times n+2 gives the concatenation of two numbers m and m-9. 5
 4622, 5377, 7980, 34952, 46865, 53134, 65047, 7056186, 9783459, 43176670, 56823329, 97999800, 447255476452, 552744523547, 755424659534, 799319866013, 997999998000, 4297663349523, 5702336650476, 6971253996227 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..1122 EXAMPLE 97999800 * 97999802 = 96039609//96039600, where // denotes concatenation. MAPLE A:= NULL: count:= 0: for d from 2 to 40 do   R:= [msolve(x^2=-8, 10^d+1)];   T:= sort(select(t -> t*(t+2) mod 10^d >= 10^(d-1), map(t -> subs(t, x-1), R)));   count:= count+nops(T);   A:= A, op(T); od: A; # Robert Israel, Jan 04 2021 CROSSREFS Cf. A116095, A116225, A116227, A116233. Sequence in context: A237634 A051649 A140175 * A115446 A254850 A139410 Adjacent sequences:  A116223 A116224 A116225 * A116227 A116228 A116229 KEYWORD nonn,base AUTHOR Giovanni Resta, Feb 06 2006 STATUS approved

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Last modified December 1 02:46 EST 2021. Contains 349426 sequences. (Running on oeis4.)