A115420 Numbers having a 1 in position 4 of their binary expansion.

16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127

Offset

1,1

Comments

One of the mystery calculator sequences: A005408, A042964, A047566, A115419, A115420, A115421.

Links

Table of n, a(n) for n=1..64.

Edd Mann, Mystery Calculator.

Example

a(1) = 16 = 10000 in binary.

Maple

a:= n-> n+15 + 16*iquo(n-1, 16):
seq(a(n), n=1..100);  # Alois P. Heinz, Aug 22 2011

Prog

(Python)
def A115420(n): return ((n-1<<1)&-15|16)+(n-1&15) # Chai Wah Wu, Mar 28 2024

Crossrefs

Cf. A005408, A042964, A047566, A115419, A115421.

Sequence in context: A190582 A004457 A248501 * A250038 A296754 A297284

Adjacent sequences: A115417 A115418 A115419 * A115421 A115422 A115423

Keyword

base,easy,nonn

Author

Jeremy Gardiner, Jan 22 2006

Status

approved