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 A338937 a(n+1) = A001414(a(n)) + A001414(a(n-1)) with a(0)=1, a(1)=2. 1
 1, 2, 2, 4, 6, 9, 11, 17, 28, 28, 22, 24, 22, 22, 26, 28, 26, 26, 30, 25, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19, 28, 30, 21, 20, 19 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Enters 5-cycle 20,19,28,30,21 starting with a(20). LINKS FORMULA a(n) = a(n-5) for n >= 25. a(n+1) = A001414(a(n)*a(n-1)). EXAMPLE a(5) = A001414(6) + A001414(4) = 5 + 4 = 9. MAPLE spf:= n -> add(t[1]*t[2], t=ifactors(n)[2]): N:= 100: A:= Array(0..N): A[0]:= 1: A[1]:= 2: for n from 2 to N do   A[n]:= spf(A[n-1])+spf(A[n-2]) od: seq(A[i], i=0..N); CROSSREFS Cf. A001414, A338938. Sequence in context: A337723 A222735 A299408 * A319381 A340496 A035564 Adjacent sequences:  A338934 A338935 A338936 * A338938 A338939 A338940 KEYWORD nonn AUTHOR J. M. Bergot and Robert Israel, Nov 16 2020 STATUS approved

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Last modified July 30 17:04 EDT 2021. Contains 346359 sequences. (Running on oeis4.)