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 A046920 Number of ways to express n as p+2a^2; p = 1 or prime, a >= 0. 6
 1, 1, 2, 1, 2, 0, 2, 0, 2, 1, 2, 0, 3, 0, 2, 0, 1, 0, 4, 1, 3, 0, 2, 0, 3, 0, 1, 0, 2, 0, 4, 0, 2, 1, 2, 0, 4, 0, 3, 0, 2, 0, 3, 0, 3, 0, 2, 0, 4, 0, 3, 1, 2, 0, 5, 0, 1, 0, 2, 0, 6, 0, 3, 0, 1, 0, 3, 0, 4, 0, 2, 0, 5, 1, 4, 0, 2, 0, 6, 0, 3, 0, 2, 0, 4, 0, 2, 0, 3, 0, 6, 0, 2, 0, 1, 0, 4, 0, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS T. D. Noe, Table of n, a(n) for n=1..10000 L. Hodges, A lesser-known Goldbach conjecture, Math. Mag., 66 (1993), 45-47. PROG (Haskell) a046920 n = length \$ filter ((\x -> x == 1 || a010051 x == 1) . (n -)) \$                             takeWhile (< n) a001105_list -- Reinhard Zumkeller, Apr 03 2013 CROSSREFS Cf. A042978, A046921, A046922, A046923, A060003, A143539. Cf. A016067, A008578, A010051, A001105. Sequence in context: A117167 A117169 A274263 * A107599 A156836 A287438 Adjacent sequences:  A046917 A046918 A046919 * A046921 A046922 A046923 KEYWORD nonn,changed AUTHOR STATUS approved

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Last modified August 3 14:40 EDT 2021. Contains 346438 sequences. (Running on oeis4.)