A353088 Primes having square prime gaps to both neighbor primes.
9551, 12889, 22193, 22307, 27143, 29917, 32261, 40423, 42863, 46807, 46993, 47981, 57637, 60041, 60493, 71597, 72613, 73819, 77137, 84263, 88427, 89153, 90583, 93463, 97463, 97613, 97883, 112543, 115057, 118931, 126307, 127877, 131321, 134093, 137873, 144883
Offset: 1
Keywords
Examples
Prime 9551 is a term, the gap to the previous prime 9547 is 4 and the gap to the next prime 9587 is 36 and both gaps are squares.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..10000
Crossrefs
Programs
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Maple
q:= n-> isprime(n) and andmap(issqr, [n-prevprime(n), nextprime(n)-n]): select(q, [$3..200000])[];
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Mathematica
q[n_] := PrimeQ[n] && IntegerQ@Sqrt[n-NextPrime[n, -1]] && IntegerQ@ Sqrt[NextPrime[n]-n]; Select[Range[3, 200000], q] (* Jean-François Alcover, May 14 2022, after Alois P. Heinz *) Select[Prime[Range[2,15000]],AllTrue[{Sqrt[#-NextPrime[#,-1]],Sqrt[NextPrime[#]-#]},IntegerQ]&] (* Harvey P. Dale, Jan 22 2024 *)
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Python
from itertools import islice from sympy import nextprime, integer_nthroot def A353088_gen(): # generator of terms p, q, g, h = 3, 5, True, False while True: if g and h: yield p p, q = q, nextprime(q) g, h = h, integer_nthroot(q-p,2)[1] A353088_list = list(islice(A353088_gen(),30)) # Chai Wah Wu, Apr 22 2022