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A108583
Primes of the form 1 + Product_{j=1..k} b(j), where b(n) = b(n-1) + 2*A005185(n) and b(1) = 2.
2
3, 13, 2593, 2426113
OFFSET
0,1
COMMENTS
Next term contains 886 digits. - G. C. Greubel, Dec 19 2022
LINKS
MATHEMATICA
Hofstadter[n_]:= Hofstadter[n]= If[n<2, 1, Hofstadter[n-Hofstadter[n- 1]] +Hofstadter[n-Hofstadter[n-2]]]; (* A005185 *)
b[n_]:= b[n]= If[n==1, 2, b[n-1] +2*Hofstadter[n]]; (* A108585 *)
p[n_]:= p[n]= Product[b[j], {j, n}];
Select[Table[p[n] +1, {n, 500}], PrimeQ]
CROSSREFS
Sequence in context: A177362 A138487 A022507 * A127855 A087333 A320041
KEYWORD
nonn,less
AUTHOR
Roger L. Bagula, Jul 05 2005
EXTENSIONS
Edited by G. C. Greubel, Dec 19 2022
STATUS
approved