%I A154280
%S A154280 0,1,1,1,2,1,4,2,6,4,9,12,13,48,17,192,21,768,26,3840,32,23040,39,
%T A154280 161280,46,1128960,54,9031680,62,72253440,70,578027520,78,4624220160,87,
%U A154280 41617981440,97,416179814400,108,4577977958400,120,54935735500800,132
%N A154280 List of pairs: {a(n),b(n)}: f(n)=A004001(n); a(n)=f(n)+a(n-1); b(n)=f(n)*b(n-1);
%C A154280 There are primes associated with the product sequence:
%C A154280 Flatten[Table[If[PrimeQ[b[n] - 1], b[n] - 1, If[PrimeQ[b[n] + 1], b[
n] + 1, {}]], {n, 0, 30}]].
%C A154280 {2, 2, 2, 3, 3, 11, 47, 191, 769, 23039, 161281, 9031681, 41617981439,
%C A154280 8569974738124801, 119979646333747199}
%F A154280 f(n)=A004001(n);
%F A154280 a(n)=f(n)+a(n-1);
%F A154280 b(n)=f(n)*b(n-1);
%t A154280 Clear[a, b, f, n];
%t A154280 (*A004001*) f[0] = 0; f[1] = 1; f[2] = 1; f[n_] := f[n] = f[f[n - 1]]
+ f[n - f[n - 1]];
%t A154280 a[0] = 0; a[n_] := a[n] = f[n] + a[n - 1];
%t A154280 b[0] = 1; b[1] = 1; b[n_] := b[n] = (f[n])*b[n - 1];
%t A154280 Flatten[Table[{a[n], b[n]}, {n, 0, 30}]]
%Y A154280 A004001
%Y A154280 Sequence in context: A107130 A065423 A008733 this_sequence A004795 A161268
A007690
%Y A154280 Adjacent sequences: A154277 A154278 A154279 this_sequence A154281 A154282
A154283
%K A154280 nonn,uned,tabf
%O A154280 0,5
%A A154280 Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Jan 06 2009
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