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A375198
Numbers k such that A025487(k)-1 and A025487(k)+1 are twin primes.
2
3, 4, 6, 9, 13, 15, 20, 21, 24, 29, 30, 42, 54, 56, 59, 72, 77, 83, 96, 104, 105, 109, 138, 161, 166, 174, 186, 203, 208, 221, 232, 237, 266, 270, 288, 295, 336, 338, 347, 387, 389, 395, 400, 401, 449, 468, 469, 472, 479, 506, 520, 543, 584, 617, 633, 643, 668
OFFSET
1,1
LINKS
FORMULA
A025487(a(n)) = A375197(n).
MATHEMATICA
Position[Cases[Import["https://oeis.org/A025487/b025487.txt", "Table"], {_, _}][[;; , 2]], _?(PrimeQ[# - 1] && PrimeQ[# + 1] &)] // Flatten
CROSSREFS
Similar sequences: A321995, A353302.
Sequence in context: A140570 A285303 A135072 * A032720 A289117 A355697
KEYWORD
nonn
AUTHOR
Amiram Eldar, Aug 04 2024
STATUS
approved