A225388 Prime powers (A025475) representable as (p+q)/2, where p and q are distinct prime powers.

25, 125, 169, 243, 256, 289, 625, 841, 1369, 1681, 2809, 3125, 3721, 5329, 9409, 11881, 12769, 18769, 22201, 28561, 37249, 38809, 54289, 76729, 83521, 100489, 113569, 151321, 160801, 196249, 201601, 208849, 292681, 323761, 375769, 390625, 410881, 426409, 452929, 502681

Offset

1,1

Links

Table of n, a(n) for n=1..40.

Example

a(1) = 25 = (1 + 49) / 2.
a(2) = 125 = (81 + 169) / 2.
a(3) = 169 = (49 + 289) / 2.
a(4) = 243 = (125 + 361) / 2.
a(5) = 256 = (169 + 343) / 2.
a(6) = 289 = (49 + 529) / 2.

Crossrefs

Cf. A025475, A225389.

Sequence in context: A172047 A304422 A280390 * A369563 A146945 A044357

Adjacent sequences: A225385 A225386 A225387 * A225389 A225390 A225391

Keyword

nonn

Author

Alex Ratushnyak, May 05 2013

Status

approved