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A132746 Numbers k such that prime(k) + prime(k+1) is a perfect power. 0
2, 7, 15, 18, 20, 28, 61, 152, 190, 293, 377, 492, 558, 564, 789, 919, 942, 1332, 1768, 2343, 2429, 2693, 2952, 3136, 3720, 3928, 4837, 5421, 5722, 6870, 7347, 8126, 8193, 9465, 9857, 9927, 10410, 10483, 10653, 12685, 13005, 13763, 13955, 16033, 16342 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

First terms absent in A064397: 2, 18, 28, 564, 1332, 3928, 12415, 13005, 16886.

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

2 is a term because prime(2) + prime(3) = 3 + 5 = 8 = 2^3 (perfect power);

7 is a term because prime(7) + prime(8) = 17 + 19 = 36 = 6^2 (perfect power);

39867 is a term because prime(39867) + prime(39868) = 478241 + 478243 = 956484 = 978^2 (perfect power).

PROG

(PARI) s=[]; for(n=1, 41530, a=prime(n)+prime(n+1); if(ispower(a), s=concat(s, n))); s

CROSSREFS

Cf. A064397 (numbers k such that prime(k) + prime(k+1) is a square).

Sequence in context: A088824 A034903 A070898 * A252475 A167543 A332495

Adjacent sequences:  A132743 A132744 A132745 * A132747 A132748 A132749

KEYWORD

nonn

AUTHOR

Zak Seidov, Nov 17 2007

STATUS

approved

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Last modified May 13 08:08 EDT 2021. Contains 343836 sequences. (Running on oeis4.)