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A276198
Smallest prime >= decimal expansion of phi truncated to n places (A011551), where phi is the golden ratio (A001622).
1
2, 17, 163, 1619, 16183, 161807, 1618033, 16180349, 161803403, 1618033999, 16180339933, 161803398917, 1618033988749, 16180339887557, 161803398874991, 1618033988749901, 16180339887498961, 161803398874989661, 1618033988749894853, 16180339887498948503, 161803398874989484891
OFFSET
0,1
LINKS
Eric Weisstein's World of Mathematics, Next Prime
Eric Weisstein's World of Mathematics, Golden Ratio
Eric Weisstein's World of Mathematics, Phi-Prime
FORMULA
a(n) = A007918(A011551(n)).
a(n) = A000040(A000720(A011551(n)-1)+1).
a(A064119(n)-1) = A064117(n).
EXAMPLE
a(5) = 161807, since this is the smallest prime >= floor(phi*10^5) = 161803.
phi = 1.61803398874989484820458683436563811772...
MATHEMATICA
Table[NextPrime[Floor[GoldenRatio 10^n] - 1], {n, 0, 20}]
KEYWORD
nonn,base
AUTHOR
Ilya Gutkovskiy, Aug 24 2016
STATUS
approved