A300164 - OEIS

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A300164

Numbers of the form n^2+1 not expressible as j^2+k^2 with j>k>1.

2, 5, 10, 17, 26, 37, 50, 82, 101, 122, 197, 226, 257, 362, 401, 577, 626, 677, 842, 1226, 1297, 1522, 1601, 1682, 2026, 2402, 2602, 2917, 3137, 3482, 3722, 4226, 4357, 4762, 5042, 5477, 6242, 7057, 7226, 8101, 8837, 9026, 10202, 12101, 13457, 14401

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Hugo Pfoertner, Table of n, a(n) for n = 1..10000

EXAMPLE

The first numbers of the form n^2 + 1 not in the sequence are:

65 = 8^2 + 1 because it can be expressed as 65 = 7^2 + 4^2,

145 = 12^2 + 1 = 9^2 + 8^2,

170 = 13^2 + 1 = 11^2 + 7^2.

CROSSREFS

Cf. A050796, A065876, A071557, A299708.

Sequence in context: A002522 A217990 A322008 * A248193 A069987 A248742

Adjacent sequences: A300161 A300162 A300163 * A300165 A300166 A300167

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Feb 27 2018

STATUS

approved