A206280 Smallest of four consecutive primes whose sum is a square.

5, 73, 137, 433, 569, 1217, 5171, 15859, 16631, 32027, 35677, 37619, 39191, 45767, 59029, 63997, 65011, 77813, 92401, 103669, 186601, 196201, 230387, 237161, 261089, 273517, 439559, 463747, 484397, 488573, 505511, 514079, 519803, 538739, 544627, 633599

Offset

1,1

Links

Table of n, a(n) for n=1..36.

Example

a(4) = 433. The next three primes are 439, 443, and 449, and the sum of those four primes = 1764 = 42^2.

Mathematica

Transpose[Select[Partition[Prime[Range[80000]], 4, 1], IntegerQ[Sqrt[ Total[#]]]&]][[1]]

Crossrefs

Cf. A061275, A206279, A206281.

Sequence in context: A319767 A341670 A138623 * A070526 A070530 A248046

Adjacent sequences: A206277 A206278 A206279 * A206281 A206282 A206283

Keyword

nonn,easy

Author

Harvey P. Dale, Feb 05 2012

Status

approved