A385700 Numbers such that when the leftmost digit is moved to the unit's place the result is divisible by 4.

0, 4, 8, 21, 23, 25, 27, 29, 40, 42, 44, 46, 48, 61, 63, 65, 67, 69, 80, 82, 84, 86, 88, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269

Offset

1,2

Links

Stefano Spezia, Table of n, a(n) for n = 1..10000

Example

263 is a term since 632 = 158*4 is divisible by 4.

Mathematica

Select[Range[0, 270], Divisible[FromDigits[RotateLeft[IntegerDigits[#]]], 4] &]

Prog

(PARI) isok(k) = if (k==0, return(1)); my(d=digits(k), v = vector(#d-1, i, d[i+1])); v = concat(v, d[1]); fromdigits(v) % 4 == 0; \\ Michel Marcus, Jul 08 2025
(Python)
def ok(n): return int((s:=str(n))[1:]+s[0])%4 == 0
print([k for k in range(270) if ok(k)]) # Michael S. Branicky, Jul 08 2025

Crossrefs

Similar sequences for k=1..9: A001477, A273892, A008585, this sequence, A217398, A385701, A385702, A385703, A008591.

Sequence in context: A209451 A102559 A308233 * A371001 A037020 A094878

Adjacent sequences: A385697 A385698 A385699 * A385701 A385702 A385703

Keyword

nonn,base,easy,look

Author

Stefano Spezia, Jul 07 2025

Status

approved