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A115171 Positive numbers that are not the sum of a triangular number, a square and a positive Fibonacci number. 10
3970902, 4851691, 7921800, 39022919, 102132857, 110468517, 368495972, 391099413, 395147912, 421129348, 452808398, 608389509, 667231451, 693386307, 698864465, 776218485, 1005771844, 1335351479, 1336652359, 1485470432 (list; graph; refs; listen; history; text; internal format)
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

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Last modified November 19 04:01 EST 2017. Contains 294912 sequences.