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A138266 Balanced prime numbers n such that n*(n+1)-1 is a balanced prime. 0
113921, 114083, 375163, 760933, 1065893, 1432583, 2362153, 2935453, 3294293, 3390719, 3591781, 3699011, 3981119, 4489273, 5371801, 5780513, 6233693, 6297223, 6470231, 6830041, 6982021, 7036193, 7164673, 7490221, 8266229, 8577623, 8608291, 8698241, 8805163 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
NextPrime[n_Int]:=Module[{k}, k=n+1; While[ !PrimeQ[k], k++ ]; k]; PrevPrime[n_Int]:=Module[{k}, k=n-1; While[ !PrimeQ[k], k-- ]; k]; s=""; For[i=2, i< 10^5*2, p=Prime[i]; If[(Prime[i-1]+Prime[i+1])/2==p, r=p*(p+1)-1; a=PrevPrime[r]; b=NextPrime[r]; If[PrimeQ[r]&&r==(a+b)/2, (*Print[p, ":", a, ", ", b, "; ", r]*)s=s<>ToString[p]<>", "]]; i++ ]; Print[s]
CROSSREFS
Cf. A006562.
Sequence in context: A112009 A034633 A253118 * A175697 A023092 A221334
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(8)-a(29) from Donovan Johnson, Aug 24 2011
STATUS
approved

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)