A115171 Positive numbers that are not the sum of a triangular number, a square and a positive Fibonacci number.

3970902, 4851691, 7921800, 39022919, 102132857, 110468517, 368495972, 391099413, 395147912, 421129348, 452808398, 608389509, 667231451, 693386307, 698864465, 776218485, 1005771844, 1335351479, 1336652359, 1485470432

Offset

1,1

Comments

Comment from Kurt Foster, Jan 20 2009: If one is allowed to use the Fibonacci number zero, then many of these terms disappear. For example, one has 4851691 = 1885^2 + 1611*1612/2 + F_0, 7921800 = 1923^2 + 2906*2907/2 + F_0. See A144642.

Since the number of integers up to B of the form x^2+T_y is about a constant times B/sqrt(log B), heuristics predict that the sequence should be infinite. - Bjorn Poonen, in a posting to the Number Theory List, Dec 22 2008

Links

Donovan Johnson, Table of n, a(n) for n = 1..176 (terms < 4*10^10)

Crossrefs

Cf. A115172, A115173, A115174, A115175, A115176, A115177, A144642.

Sequence in context: A253406 A251071 A184562 * A144642 A032753 A047987

Adjacent sequences: A115168 A115169 A115170 * A115172 A115173 A115174

Keyword

nonn

Author

Giovanni Resta, Jan 15 2006

Status

approved