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Even numbers that are the sum of two squares; also numbers which are twice the sum of two squares.

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`%I #12 Jul 01 2022 04:58:36
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`%S 0,2,4,8,10,16,18,20,26,32,34,36,40,50,52,58,64,68,72,74,80,82,90,98,
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`%T 100,104,106,116,122,128,130,136,144,146,148,160,162,164,170,178,180,
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`%U 194,196,200,202,208,212,218,226,232,234,242,244,250,256,260,272,274,288,290,292,296,298,306,314,320
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`%N Even numbers that are the sum of two squares; also numbers which are twice the sum of two squares.
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`%C This is both the even subsequence of A001481, and twice A001481. It is an easy exercise to show that these two definitions produce the same sequence.
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`%o (Python)
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`%o from itertools import count, islice
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`%o from sympy import factorint
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`%o def A354776_gen(): # generator of terms
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`%o return filter(lambda n:(lambda m:all(d & 3 != 3 or m[d] & 1 == 0 for d in m))(factorint(n//2)),count(0,2))
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`%o A354776_list = list(islice(A354776_gen(),30)) # _Chai Wah Wu_, Jun 27 2022
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`%Y Cf. A001481. Essentially the same as A128106.
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`%K nonn
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`%O 1,2
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`%A _N. J. A. Sloane_, Jun 26 2022, following a suggestion from _Charles Kusniec_.
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