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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.
4
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
OFFSET
1,1
COMMENTS
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,...
LINKS
PROG
(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
print(aupton(45)) # Michael S. Branicky, Dec 03 2021
CROSSREFS
Cf. A000069 (odious), A001969 (evil), A248009, A248138, A248140, A248172 (similar, with odious).
Sequence in context: A040139 A317312 A112033 * A258227 A130895 A367431
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Oct 03 2014
EXTENSIONS
More terms from Peter J. C. Moses, Oct 04 2014
STATUS
approved