A116301 n times n+1 gives the concatenation of two numbers m and m+2.

768, 859, 911, 3286, 6714, 45453, 54547, 990101, 8181820, 70588234, 343130555, 362637364, 363636362, 420053632, 421052633, 497975710, 502024290, 578947367, 579946368, 636363638, 637362636, 656869445, 706766919

Offset: 1

Author

Giovanni Resta, Feb 06 2006

Keywords

• nonn
• base

Links

• Robert Israel, Table of n, a(n) for n = 1..9000

Crossrefs

Cf. A116170, A116294, A116302, A116307.

Programs

Maple

As:= {}:
for m from 2 to 20 do
   acands:= map(t -> rhs(op(t)), [msolve(a*(a+1)=2, 10^m+1)]);
   bcands:= map(t -> t*(t+1) mod 10^m, acands);
   good:= select(t -> bcands[t]>=10^(m-1), [$1..nops(acands)]);
   As:= As union convert(acands[good],set);
od:
sort(convert(As,list)); # Robert Israel, Aug 20 2019