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%I #17 Aug 03 2023 04:11:28
%S 1,7,13,19,23,28,44,49,68,79,129,133,139,167,188,226,236,239,338,356,
%T 367,368,379,446,469,478,556,566,888,899,1112,1114,1115,1122,1125,
%U 1128,1148,1158,1177,1188,1222,1233,1247,1257,1258,1277,1288,1299,1333,1335
%N Happy numbers without zeros and with digits in nondecreasing order.
%H Bryan Wolf, <a href="/A124095/b124095.txt">Table of n, a(n) for n = 0..13376</a> (terms < 10^10))
%H Bryan Wolf, <a href="/A124095/a124095.cpp.txt">C++ program for generating happy numbers without zeros and with digits in non-decreasing order</a>
%o (Python)
%o from itertools import count, islice, combinations_with_replacement
%o def A124095_gen(): # generator of terms
%o for l in count(1):
%o for m in combinations_with_replacement('123456789',l):
%o k = t = int(''.join(m))
%o while k not in {1,37,58,89,145,42,20,4,16}:
%o k = sum((0, 1, 4, 9, 16, 25, 36, 49, 64, 81)[ord(d)-48] for d in str(k))
%o if k == 1:
%o yield t
%o A124095_list = list(islice(A124095_gen(),20)) # _Chai Wah Wu_, Aug 02 2023
%Y Cf. A007770 (Happy numbers), A068571, A219667.
%K base,nonn
%O 0,2
%A _Tanya Khovanova_, Nov 25 2006
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