A082078 Balanced primes of order three.
17, 53, 157, 173, 193, 229, 349, 439, 607, 659, 701, 709, 977, 1153, 1187, 1301, 1619, 2281, 2287, 2293, 2671, 2819, 2843, 3067, 3313, 3539, 3673, 3727, 3833, 4013, 4051, 4517, 4951, 5101, 5897, 6079, 6203, 6211, 6323, 6679, 6869, 7321, 7589, 7643, 7907
Offset: 1
Keywords
Examples
p = 53 = (41 + 43 + 47 + 53 + 59 + 61 + 67)/7 = 371/7 i.e. it is the arithmetic mean.
Links
- Aaron Toponce, Table of n, a(n) for n = 1..1000
Crossrefs
Programs
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GAP
P:=Filtered([1..10000],IsPrime);; a:=List(Filtered(List([0..1000],k->List([4..10],j->P[j-3+k])), i-> Sum(i)/7=i[4]),m->m[4]); # Muniru A Asiru, Feb 14 2018
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Mathematica
Do[s3=Prime[n]+Prime[n+1]+Prime[n+2]; s5=Prime[n-1]+s3+Prime[n+3]; s7=Prime[n-2]+s5+Prime[n+4]; If[Equal[s7/7, Prime[n+1]], Print[Prime[n+1]]], {n, 3, 5000}] (* Second program: *) With[{k = 3}, Select[MapIndexed[{Prime[First@ #2 + k], #1} &, Mean /@ Partition[Prime@ Range[10^3], 2 k + 1, 1]], SameQ @@ # &][[All, 1]]] (* Michael De Vlieger, Feb 15 2018 *) Select[Partition[Prime[Range[1500]],7,1],Mean[#]==#[[4]]&][[All,4]] (* Harvey P. Dale, Jul 01 2022 *)
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PARI
isok(p) = {if (isprime(p), k = primepi(p); if (k > 3, sum(i=k-3, k+3, prime(i)) == 7*p;););} \\ Michel Marcus, Mar 07 2018
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