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A379158
Numbers m such that the consecutive prime powers A246655(m) and A246655(m+1) are both prime.
2
1, 4, 8, 11, 12, 16, 19, 20, 21, 24, 25, 28, 29, 30, 33, 34, 35, 36, 37, 38, 39, 45, 46, 47, 48, 49, 50, 51, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 71, 72, 73, 74, 75, 76, 79, 80, 81, 82, 83, 84, 87, 88, 89, 92, 93, 94, 95, 96, 97, 98, 99, 100
OFFSET
1,2
COMMENTS
Also positions of 2 in A366835.
FORMULA
A246655(a(n)) = A379541(n).
EXAMPLE
The 4th and 5th prime powers are 5 and 7, which are both prime, so 4 is in the sequence.
The 12th and 13th prime powers are 19 and 23, which are both prime, so 12 is in the sequence.
MATHEMATICA
v=Select[Range[100], PrimePowerQ];
Select[Range[Length[v]-1], PrimeQ[v[[#]]]&&PrimeQ[v[[#+1]]]&]
CROSSREFS
Positions of adjacent primes in A246655 (prime powers).
Positions of 2 in A366835.
For just one prime we have A379155, positions of prime powers in A379157.
For no primes we have A379156, positions of prime powers in A068315.
The primes powers themselves are A379541.
A000015 gives the least prime power >= n.
A000040 lists the primes, differences A001223.
A000961 lists the powers of primes, differences A057820.
A031218 gives the greatest prime power <= n.
A065514 gives the greatest prime power < prime(n), difference A377289.
A131605 finds perfect powers that are not prime powers.
A366833 counts prime powers between primes, see A053607, A304521.
Sequence in context: A311017 A311018 A098019 * A288150 A311019 A068798
KEYWORD
nonn
AUTHOR
Gus Wiseman, Dec 23 2024
STATUS
approved