A080470 -id:A080470 - cp's OEIS frontend

A080471 a(n) is the smallest Fibonacci number that is obtained by placing digits anywhere in n; a(n) = n if n is a Fibonacci number.

1, 2, 3, 34, 5, 610, 377, 8, 89, 610, 4181, 121393, 13, 144, 1597, 10946, 1597, 4181, 1597, 832040, 21, 514229, 233, 2584, 2584, 28657, 28657, 2584, 121393, 832040, 317811, 832040, 233, 34, 3524578, 46368, 377, 46368, 121393, 832040, 4181, 514229

Offset: 1

Amarnath Murthy, Mar 07 2003

Robert Israel, Table of n, a(n) for n = 1..10000

Cf. A068164, A068165, A080470.

IsSubList:= proc(T, S)
  local i;
  if T = [] then return true fi;
  if S = [] then return false fi;
  i:= ListTools:-Search(T[1],S);
  if i = 0 then false else procname(T[2..-1],S[i+1..-1]) fi
end proc:
f:= proc(n) local T,S,k,v;
   T:= convert(n,base,10);
   for k from 1 do
      v:= combinat:-fibonacci(k);
      S:= convert(v,base,10);
      if IsSubList(T,S) then return v fi
   od
end proc:
map(f, [$1..100]); # Robert Israel, Mar 10 2020

a[n_] := Block[{p = RegularExpression[ StringJoin @@ Riffle[ ToString /@ IntegerDigits[ n], ".*"]], f, k=2}, While[! StringContainsQ[ ToString[f = Fibonacci[ k++]], p]]; f]; Array[a, 42] (* Giovanni Resta, Mar 10 2020 *)

def dmo(n, t):
    if t < n: return False
    while n and t:
        if n%10 == t%10:
            n //= 10
        t //= 10
    return n == 0
def fibo(f=1, g=2):
    while True: yield f; f, g = g, f+g
def a(n):
    return next(f for f in fibo() if dmo(n, f))
print([a(n) for n in range(1, 77)]) # Michael S. Branicky, Jan 21 2023

Corrected and extended by Ray Chandler, Oct 11 2003

A080472 a(n) = smallest triangular number that is obtained by placing digits anywhere in n; a(n) = n if n is a triangular number.

Original entry on oeis.org

1, 21, 3, 45, 15, 6, 78, 28, 91, 10, 171, 120, 136, 1431, 15, 136, 171, 1081, 190, 120, 21, 1225, 231, 2145, 253, 276, 276, 28, 2926, 300, 231, 325, 3003, 2346, 325, 36, 378, 378, 3916, 406, 741, 4278, 435, 4465, 45, 406, 4278, 1485, 496, 1540, 351, 528, 153, 1540

Offset: 1

Amarnath Murthy, Mar 07 2003

Michael S. Branicky, Table of n, a(n) for n = 1..10000

Cf. A068164, A068165, A080470, A080471.

from math import isqrt
from itertools import count
def dmo(n, t):
    if t < n: return False
    while n and t:
        if n%10 == t%10:
            n //= 10
        t //= 10
    return n == 0
def a(n):
    return next(t for t in (i*(i+1)//2 for i in count(isqrt(2*n))) if dmo(n, t))
print([a(n) for n in range(1, 77)]) # Michael S. Branicky, Jan 21 2023

More terms from Ray Chandler, Oct 11 2003

cp's OEIS Frontend

A080471 a(n) is the smallest Fibonacci number that is obtained by placing digits anywhere in n; a(n) = n if n is a Fibonacci number.

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