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A270231
Smaller member of a twin prime pair with a perfect power sum.
4
3, 17, 71, 107, 881, 1151, 2591, 3527, 4049, 15137, 20807, 34847, 46817, 69191, 83231, 103967, 112337, 139967, 149057, 176417, 179999, 206081, 281249, 362951, 388961, 438047, 472391, 478241, 538721, 649799, 734471, 808991, 960497, 1080449, 1143071, 1152161, 1254527
OFFSET
1,1
COMMENTS
A069496 is a subsequence.
LINKS
EXAMPLE
3 is a term because 3 + 5 = 2^3.
17 is a term because 17 + 19 = 6^2.
107 is a term because 107 + 109 = 6^3.
139967 is a term because 139967 + 139969 = 6^7.
PROG
(PARI) t(n, p=3) = { while( p+2 < (p=nextprime( p+1 )) || n-->0, ); p-2}
for(n=1, 1e4, if(ispower(2*t(n)+2), print1(t(n), ", ")));
(Magma) [p:p in PrimesUpTo(1300000)|IsPrime(p+2) and IsPower(2*p+2)]; // Marius A. Burtea, Dec 20 2019
CROSSREFS
First bisection of A119768.
Sequence in context: A357923 A069468 A241776 * A265919 A317452 A128948
KEYWORD
nonn
AUTHOR
Altug Alkan, Mar 13 2016
STATUS
approved