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Peter
Peter
1:49 PM
For which positive integers $n$ is $F_n+n$ a prime number ($F_n$ is the $n$ th Fibonacci number) ? The first such $n's$ are :
1 2 3 4 8 9 28 33 38 808 1642
F(808)+808
F(1642)+1642
F(13288)+13288
F(20434)+20434
PRP 6061 (show) I(29001)+29001<6061> = 3170077556...27<6061>
 
 
3 hours later…
Peter
Peter
4:58 PM
PRP 11991 (show) I(57374)+57374<11991> = 1280520985...31<11991>
current search limit : $94\ 000$
 
 
2 hours later…
Peter
Peter
6:39 PM
Summary :
F(28)+28
F(33)+33
F(38)+38
F(808)+808
F(1642)+1642
F(13288)+13288
F(20434)+20434
F(29001)+29001
F(57374)+57374
CurLineExpr=F(108844)+108844
 

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