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

0,4

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.

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 *)

Prog

(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

Crossrefs

Cf. A000045, A001129, A014259, A014260.

Sequence in context: A004091 A072210 A273003 * A237575 A275524 A177195

Adjacent sequences: A014255 A014256 A014257 * A014259 A014260 A014261

Keyword

nonn,base,easy

Author

N. J. A. Sloane

Status

approved