A373262 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give

A373262

Numbers k for which A276085(k) == -1 (mod 3), where A276085 is the primorial base log-function.

3, 4, 15, 18, 20, 21, 24, 28, 32, 33, 39, 44, 51, 52, 57, 68, 69, 75, 76, 81, 87, 90, 92, 93, 100, 105, 108, 111, 116, 120, 123, 124, 126, 129, 140, 141, 144, 147, 148, 159, 160, 164, 165, 168, 172, 177, 183, 188, 192, 195, 196, 198, 201, 212, 213, 219, 220, 224, 231, 234, 236, 237, 244, 249, 255, 256, 260, 264, 267

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Numbers k such that the 2-adic valuation of k minus the 3-adic valuation of k is equal to -1 modulo 3.

When terms are multiplied by 2, forms a subsequence of A339746 (its even terms), and when multiplied by 3, forms a subsequence of A373261 (its multiples of 3).

More widely stated, the sequence lists one part of a 3-part partition of the positive integers with a symmetric relationship between the parts (further explained in the 2021 comment in A339746). - Peter Munn, Jul 19 2024

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

{k such that A007814(k)-A007949(k) == -1 (mod 3)}.

PROG

(PARI) isA373262 = A373263;

CROSSREFS

Cf. A007814, A007949, A276085, A373263 (characteristic function).

Positions of -1's in A373153.

The positive integers are partitioned between A339746, A373261, and this sequence.

Sequence in context: A285475 A341779 A136641 * A325186 A053359 A056742

Adjacent sequences: A373259 A373260 A373261 * A373263 A373264 A373265

KEYWORD

nonn

AUTHOR

Antti Karttunen, May 30 2024

STATUS

approved