The On-Line Encyclopedia of Integer Sequences (OEIS)

Revisions by N. J. A. Sloane

(See also N. J. A. Sloane's wiki page
and changes approved by N. J. A. Sloane)

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A089580

Total number of perfect powers > 1 below 10^n, counting multiple representations separately.
(history; published version)

#64 by N. J. A. Sloane at Fri Mar 07 11:35:02 EST 2025

STATUS

proposed

approved

A381500

a(n) = A019565(A187769(n)).
(history; published version)

#16 by N. J. A. Sloane at Fri Mar 07 11:34:17 EST 2025

STATUS

proposed

approved

Discussion

Fri Mar 07

11:34

OEIS Server: Installed first b-file as b381500.txt.

A381764

Nearest integer not equal to n with the same Hamming weight (number of 1 bits) as n.
(history; published version)

#9 by N. J. A. Sloane at Fri Mar 07 09:26:19 EST 2025

STATUS

editing

approved

#8 by N. J. A. Sloane at Fri Mar 07 09:25:54 EST 2025

COMMENTS

a(n) = integer m nearest to n such that m <> n and A000120(n) = A000120(m). In case of a tie, choose the smaller number.

STATUS

proposed

editing

Discussion

Fri Mar 07

09:26

N. J. A. Sloane: I added an "escape clause"

A380874

Indices of odd values > 1 in A067044 (least k such that k*n has only even digits).
(history; published version)

#4 by N. J. A. Sloane at Fri Mar 07 09:24:12 EST 2025

STATUS

proposed

approved

A381112

a(1) = 1, let q = greatest prime in S(n) = {p; p = A053669(a(i)); 1 <= i <= n-1}. Then for n > 1, a(n) is the smallest number not yet in the sequence such that: (i) q|a(n), and (ii) p a prime and p^k|a(n) implies p in S(n) and k <= cardinality of p in S(n).
(history; published version)

#19 by N. J. A. Sloane at Fri Mar 07 09:21:57 EST 2025

STATUS

proposed

approved

Discussion

Fri Mar 07

09:21

OEIS Server: Installed first b-file as b381112.txt.

A380670

Population of elementary triangular automaton rule 182, from a lone 1 cell.
(history; published version)

#14 by N. J. A. Sloane at Fri Mar 07 09:19:19 EST 2025

STATUS

editing

proposed

Discussion

Fri Mar 07

13:26

Paul Cousin: Sure! I'll update the other sequences on this topic.

#13 by N. J. A. Sloane at Fri Mar 07 09:18:35 EST 2025

NAME

Population of elementary triangular automaton rule 182, at generation n, starting from a lone 1 cell at generation 0.

STATUS

proposed

editing

Discussion

Fri Mar 07

09:19

N. J. A. Sloane: I propose a less cryptic definition, OK?

A381109

a(n) = (21*n^2 + 9*n + 2)/2.
(history; published version)

#39 by N. J. A. Sloane at Fri Mar 07 09:15:32 EST 2025

STATUS

proposed

approved

A087713

Greatest prime factor of the product of the neighbors of the n-th prime.
(history; published version)

#27 by N. J. A. Sloane at Fri Mar 07 09:14:21 EST 2025

STATUS

proposed

approved