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 A131697 Prime averages of two successive perfect prime powers. 1
 101, 577, 677, 2203, 15877, 22501, 25609, 32401, 42061, 57601, 72901, 181501, 228211, 324901, 378229, 394393, 462409, 695581, 804709, 1664101, 1742401, 1971241, 2873029, 3062509, 3186229, 4137181, 4305661, 4347229, 4804889, 5336101, 6200269, 6502501, 7177693, 7209229 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..1000 EXAMPLE 101 is the average of 81 and 121. MATHEMATICA a = Select[ Range[2, 10000000], ! PrimeQ[ # ] && Length[FactorInteger[ # ]] == 1 &]; sizea = Length[a]; (a[[Select[Range[sizea - 1], PrimeQ[(a[[ # ]] + a[[ # + 1]])/2] &]]] + a[[Select[Range[sizea - 1], PrimeQ[(a[[ # ]] + a[[ # + 1]])/2] &] + 1]])/2 CROSSREFS Cf. A000961, A075455 (Prime averages of two successive perfect powers). Sequence in context: A142692 A060012 A142507 * A153806 A227521 A364147 Adjacent sequences: A131694 A131695 A131696 * A131698 A131699 A131700 KEYWORD nonn AUTHOR Tanya Khovanova, Sep 15 2007 EXTENSIONS More terms from Amiram Eldar, Feb 18 2022 STATUS approved

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Last modified June 23 17:30 EDT 2024. Contains 373653 sequences. (Running on oeis4.)