A014258 Iccanobif numbers: add previous two terms and reverse the sum.

0, 1, 1, 2, 3, 5, 8, 31, 93, 421, 415, 638, 3501, 9314, 51821, 53116, 739401, 715297, 8964541, 8389769, 1345371, 415379, 570671, 50689, 63126, 518311, 734185, 6942521, 6076767, 88291031, 89776349, 83760871, 22735371, 242694601, 279924562, 361916225, 787048146

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• base
• easy

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..1000 (first 200 terms from N. J. A. Sloane)
• N. J. A. Sloane, Transforms.

Crossrefs

Cf. A000045, A001129, A014259, A014260.

Programs

Maple

with(transforms); f:=proc(n) option remember; if n <= 1 then n else digrev(f(n-1)+f(n-2)); fi; end; [seq(f(n),n=0..50)];

Mathematica

Clear[ BiF ]; BiF[ 0 ]=0; BiF[ 1 ]=1; BiF[ n_Integer ] := BiF[ n ]=Plus@@(IntegerDigits[ BiF[ n-2 ]+BiF[ n-1 ], 10 ]//(#*Array[ 10^#&, Length[ # ], 0 ])&); Array[ BiF, 40, 0 ]
nxt[{a_,b_}]:={b,FromDigits[Reverse[IntegerDigits[a+b]]]}; Transpose[ NestList[ nxt,{0,1},40]][[1]] (* Harvey P. Dale, Jun 15 2013 *)

Python

from itertools import islice
def A014258_gen(): # generator of terms
    a, b = 0, 1
    yield 0
    while True:
        yield b
        a, b = b, int(str(a+b)[::-1])
A014358_list = list(islice(A014258_gen(),20)) # Chai Wah Wu, Jan 15 2022