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A248171 Partition of the positive integers on minimal blocks such that concatenation of numbers in each block is an evil number (A001969). Sequence lists the evil numbers obtained in this way.

%I A248171 #30 May 06 2022 13:13:51
%S A248171 12,3,45,6,78,9,10,1112,1314,15,161718,1920,2122,23,24,2526,27,2829,
%T A248171 30,3132,33,34,3536,37383940,414243,4445464748,495051,52535455,5657,
%U A248171 58,5960,6162,63,646566,6768,6970,71,72,7374,75,7677787980,818283,8485868788,89,90
%N A248171 Partition of the positive integers on minimal blocks such that concatenation of numbers in each block is an evil number (A001969). Sequence lists the evil numbers obtained in this way.
%C A248171 The numbers of the consecutive positive integers over blocks of the partition are 2,1,2,1,2,1,1,2,2,1,3,2,2,1,1,2,1,...
%H A248171 Peter J. C. Moses, <a href="/A248171/b248171.txt">Table of n, a(n) for n = 1..1000</a>
%o A248171 (Python)
%o A248171 from itertools import count
%o A248171 def evil(n): return bin(n)[2:].count('1') % 2 == 0
%o A248171 def aupton(terms):
%o A248171     alst, t = [], 0
%o A248171     for k in count(1):
%o A248171         t = int(str(t) + str(k))
%o A248171         if evil(t):
%o A248171             alst.append(t)
%o A248171             t = 0
%o A248171             if len(alst) >= terms: return alst
%o A248171 print(aupton(45)) # _Michael S. Branicky_, Dec 03 2021
%Y A248171 Cf. A000069 (odious), A001969 (evil), A248009, A248138, A248140, A248172 (similar, with odious).
%K A248171 nonn,base
%O A248171 1,1
%A A248171 _Vladimir Shevelev_, Oct 03 2014
%E A248171 More terms from _Peter J. C. Moses_, Oct 04 2014