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Concatenate first n terms of A007770 in reverse order.
1

%I #10 Dec 30 2022 20:22:54

%S 1,71,1071,131071,19131071,2319131071,282319131071,31282319131071,

%T 3231282319131071,443231282319131071,49443231282319131071,

%U 6849443231282319131071,706849443231282319131071,79706849443231282319131071,8279706849443231282319131071,868279706849443231282319131071

%N Concatenate first n terms of A007770 in reverse order.

%D Shyam Sunder Gupta, Smarandache Sequence of Happy Numbers, Smarandache Notions Journal, Vol. 13 (2002).

%e a(3)=1071 because 10,7,1 are consecutive terms of A007770 in reverse order.

%Y Cf. A007770.

%K easy,base,nonn,less

%O 1,2

%A _Shyam Sunder Gupta_, Jun 08 2002

%E a(11) and following corrected by _Georg Fischer_, Dec 30 2022