%I #17 May 28 2020 05:30:51
%S 31,129,192,262,301,319,367,391,565,622,637,655,912,931,1029,1092,
%T 1114,1121,1151,1184,1211,1221,1257,1274,1299,1332,1447,1474,1511,
%U 1527,1574,1581,1724,1744,1754,1771,1784,1814,1851,1874,1880,1881,1902,1929,2062
%N Lower of pair of consecutive happy numbers.
%D R. K. Guy, Unsolved Problems Number Theory, Sect. E34.
%H Amiram Eldar, <a href="/A035502/b035502.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HappyNumber.html">Happy Number</a>
%t f[n_] := Total[IntegerDigits[n]^2]; t = Select[Range[5000], NestWhile[f, #, UnsameQ, All] == 1 &]; t[[Select[Range[Length[t] - 1], t[[#]] == t[[# + 1]] - 1 &]]] (* _T. D. Noe_, Aug 23 2011 *)
%Y Cf. A007770, A035503.
%K nonn,easy,base
%O 1,1
%A _N. J. A. Sloane_.
%E More terms from _Sascha Kurz_, Mar 24 2002
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