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A248171
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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.
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4
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12, 3, 45, 6, 78, 9, 10, 1112, 1314, 15, 161718, 1920, 2122, 23, 24, 2526, 27, 2829, 30, 3132, 33, 34, 3536, 37383940, 414243, 4445464748, 495051, 52535455, 5657, 58, 5960, 6162, 63, 646566, 6768, 6970, 71, 72, 7374, 75, 7677787980, 818283, 8485868788, 89, 90
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OFFSET
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1,1
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COMMENTS
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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,...
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LINKS
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PROG
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(Python)
from itertools import count
def evil(n): return bin(n)[2:].count('1') % 2 == 0
def aupton(terms):
alst, t = [], 0
for k in count(1):
t = int(str(t) + str(k))
if evil(t):
alst.append(t)
t = 0
if len(alst) >= terms: return alst
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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