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A133604
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Elements of A005282 that are also the sum of a pair of not necessarily distinct elements of A005282.
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2
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2, 4, 8, 21, 66, 97, 204, 565, 662, 775, 970, 1821, 2780, 6374, 8730, 8942, 10898, 24596, 55307, 67189, 79047, 84345, 164868, 231694, 233570, 234619, 271511, 298414, 433973, 474668, 475800, 567408, 829129, 839728, 889285, 1394240
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OFFSET
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1,1
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COMMENTS
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A005282 is the sequence of smallest numbers such that the pairwise sums of not necessarily distinct elements are all distinct.
Conjecture: 2, 4 and 8 are the only terms n such that n = 2*A005282(k) for some k.
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LINKS
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EXAMPLE
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PROG
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(Python)
from itertools import count, islice
def A133604_gen(): # generator of terms
aset2, alist = set(), []
for k in count(1):
bset2 = {r:=k<<1}
if r not in aset2:
for d in alist:
if (m:=d+k) in aset2:
break
bset2.add(m)
else:
if k in aset2:
yield k
alist.append(k)
aset2.update(bset2)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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