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%I #9 May 28 2020 05:28:04
%S 2,3,2,5,6,7,8,3,7,11,12,13,14,15,2,17,2,5,2,21,22,23,24,5,26,27,28,3,
%T 2,31,32,33,3,35,6,31,38,39,40,13,42,43,44,45,46,47,48,7,50,51,52,31,
%U 54,53,56,57,58,59,54,61,62,63,8,65,66,67,12,69,70,71,72
%N Smallest happy number > 1 in base n.
%H Amiram Eldar, <a href="/A161871/b161871.txt">Table of n, a(n) for n = 2..1001</a>
%t happyQ[n_, b_] := NestWhile[Plus @@ (IntegerDigits[#, b]^2) &, n, UnsameQ, All] == 1; a[b_] := Module[{k=2}, While[!happyQ[k,b], k++]; k]; Array[a, 100, 2] (* _Amiram Eldar_, May 28 2020 *)
%Y Cf. A007770 (happy numbers in base 10).
%K nonn,base
%O 2,1
%A _Jud McCranie_, Jun 20 2009