A380490 Replace prime digits of n by 0's.

1, 0, 0, 4, 0, 6, 0, 8, 9, 10, 11, 10, 10, 14, 10, 16, 10, 18, 19, 0, 1, 0, 0, 4, 0, 6, 0, 8, 9, 0, 1, 0, 0, 4, 0, 6, 0, 8, 9, 40, 41, 40, 40, 44, 40, 46, 40, 48, 49, 0, 1, 0, 0, 4, 0, 6, 0, 8, 9, 60, 61, 60, 60, 64, 60, 66, 60, 68, 69, 0, 1, 0, 0, 4, 0, 6, 0, 8, 9, 80, 81, 80

Offset

1,4

Links

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

Formula

a(A084984(n)) = A084984(n).

a(A046034(n)) = 0.

Example

n = 7: 7 --> 0, thus a(7) = 0.
n = 26: 26 --> 06, thus a(26) = 6.
n = 472: 472 --> 400, thus a(472) = 400.

Maple

f:= proc(n) local L, i;
  L:= convert(n, base, 10);
  add(`if`(isprime(L[i]), 0, L[i]) * 10^(i-1), i=1..nops(L))
end proc:
map(f, [$1..100]); # Robert Israel, May 18 2025

Mathematica

a[n_] := FromDigits[IntegerDigits[n] /. _?PrimeQ -> 0]; Array[a, 100] (* Amiram Eldar, Jan 25 2025 *)

Prog

(Python)
def a(n): return int(str(n).translate({50:48, 51:48, 53:48, 55:48}))
print([a(n) for n in range(1, 83)]) # Michael S. Branicky, Jan 25 2025

Crossrefs

Cf. A046034, A084984.

Sequence in context: A037282 A191558 A075083 * A179939 A163407 A023891

Adjacent sequences: A380487 A380488 A380489 * A380491 A380492 A380493

Keyword

nonn,base,look

Author

Ctibor O. Zizka, Jan 25 2025

Status

approved