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A214412 Numbers that can't be expressed as the sum of a Fibonacci number and a square of a positive integer. 1
0, 8, 13, 15, 20, 23, 31, 32, 34, 40, 42, 45, 47, 48, 53, 55, 58, 60, 61, 63, 68, 73, 74, 75, 76, 78, 79, 87, 88, 92, 95, 96, 97, 99, 106, 107, 109, 110, 111, 112, 116, 117, 118, 120, 127, 128, 130, 131, 132, 133, 135, 137, 139, 140, 141, 143, 150, 151, 154, 156 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

0 is considered to be a Fibonacci number.

LINKS

Table of n, a(n) for n=1..60.

MATHEMATICA

nn = 156; sq = Range[Sqrt[nn]]^2; fb = {}; i = 0; While[f = Fibonacci[i];  f < nn, i++; AppendTo[fb, f]]; fb = Union[fb]; Complement[Range[0, nn], Union[Flatten[Outer[Plus, sq, fb]]]] (* T. D. Noe, Jul 31 2012 *)

PROG

(Python)

prpr = 0

prev = 1

fib = [0]*100

for n in range(100):

    fib[n] = prpr

    curr = prpr+prev

    prpr = prev

    prev = curr

#print fib[n]

for n in range(777):

    i = 1

    yes = 0

    while i*i<=n:

        r = n - i*i

        if r in fib:

            yes = 1

            break

        i += 1

    if yes==0:

        print n,

CROSSREFS

Cf. A000045, A132144, A214410.

Sequence in context: A252458 A271720 A243436 * A080361 A054295 A328241

Adjacent sequences:  A214409 A214410 A214411 * A214413 A214414 A214415

KEYWORD

nonn,easy

AUTHOR

Alex Ratushnyak, Jul 16 2012

STATUS

approved

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Last modified January 27 04:57 EST 2020. Contains 331291 sequences. (Running on oeis4.)