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A132929
Averages of twin primes such that the sum of the lower, average and upper parts of the twin primes are averages of other twin primes.
3
4, 6, 60, 270, 1950, 3000, 6360, 11490, 11550, 14550, 18540, 19890, 21840, 31080, 32910, 32970, 33330, 33600, 42570, 42840, 50460, 53550, 58110, 68880, 70200, 74610, 79230, 80910, 93810, 96330, 98910, 104310, 109140, 114600, 121020, 125790
OFFSET
1,1
LINKS
FORMULA
From Wesley Ivan Hurt, May 03 2022: (Start)
a(n) = A174920(n) + 1.
a(n) = A177336(n) - 1. (End)
EXAMPLE
4 is a term since (3, 5) are twin primes, 3 + 4 + 5 = 12 and (11, 13) are also twin primes.
6 is a term since (5, 7) are twin primes, 5 + 6 + 7 = 18 and (17, 19) are also twin primes.
MATHEMATICA
TwinPrimeAverageQ[n_]:=If[PrimeQ[n-1]&&PrimeQ[n+1], True, False](*TwinPrimeAverageQ*) lst={}; Do[If[TwinPrimeAverageQ[n], If[TwinPrimeAverageQ[3*n], (*Print[n]; *)AppendTo[lst, n]]], {n, 9!}]; lst
CROSSREFS
Cf. A014574.
Sequence in context: A089630 A058162 A244388 * A154668 A363861 A189790
KEYWORD
nonn
AUTHOR
STATUS
approved