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Revision History for A330687 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
Positions of records in A050377, number of ways to factor n into "Fermi-Dirac primes" (A050376).
(history; published version)
#39 by Michael De Vlieger at Sat Nov 04 21:52:23 EDT 2023
STATUS

proposed

approved

#38 by Jon E. Schoenfield at Sat Nov 04 21:44:33 EDT 2023
STATUS

editing

proposed

#37 by Jon E. Schoenfield at Sat Nov 04 21:44:30 EDT 2023
LINKS

David A. Corneth, <a href="/A330687/b330687.txt">Table of n, a(n) for n = 1..1004</a> (terms <= 10^100; first 294 terms from Antti Karttunen, terms <= 10^100)

STATUS

approved

editing

#36 by OEIS Server at Fri Jan 31 16:07:32 EST 2020
LINKS

David A. Corneth, <a href="/A330687/b330687_1.txt">Table of n, a(n) for n = 1..1004</a> (first 294 terms from Antti Karttunen, terms <= 10^100)

#35 by Sean A. Irvine at Fri Jan 31 16:07:32 EST 2020
STATUS

editing

approved

Discussion
Fri Jan 31
16:07
OEIS Server: Installed new b-file as b330687.txt.  Old b-file is now b330687_1.txt.
#34 by Sean A. Irvine at Fri Jan 31 16:07:28 EST 2020
COMMENTS

Each term is a perfect square. Proof: A050377(n) is multiplicative with a(p^e) = A018819(e) and A018819(2k) = A018819(2k+1) and this sequence considers just records so we only need exponents of the form 2k, ; i.e., terms are squares.

STATUS

proposed

editing

#33 by Jon E. Schoenfield at Wed Jan 01 15:36:14 EST 2020
STATUS

editing

proposed

#32 by Jon E. Schoenfield at Wed Jan 01 15:36:07 EST 2020
COMMENTS

More specifically: Let S(n) be the list, possibly with duplicates , of exponents occurring in the prime factorizations of terms with the sum of exponents in the prime factorization <= n.

For example, S(8) is found from the following terms: 4, 16, 64, 144, 256, 576 and 1296 as the exponents in the prime factorization are (2), (4), (6), (4, 2), (8), (6, 2), (4, 4). The sums of each of these exponents per term is <= 8. There are 10 exponents listed. Of these 10 there are 5 of them that are divisible by 4. Therefore R(8) = 5/10.

STATUS

proposed

editing

Discussion
Wed Jan 01
15:36
Jon E. Schoenfield: Okay like this?
#31 by David A. Corneth at Mon Dec 30 18:11:34 EST 2019
STATUS

editing

proposed

#30 by David A. Corneth at Mon Dec 30 18:11:07 EST 2019
COMMENTS

It seems that most exponents of a(n) are divisible by 4. (End)

More specifically: Let S(n) be the list, possibly with duplicates of exponents occurring in the prime factorizations of terms with the sum of exponents in the prime factorization <= n.

Let R(n) = |{x : x==4, S(n)}| / |S(n)|.

For example, S(8) is found from the following terms: 4, 16, 64, 144, 256, 576 and 1296 as the exponents in the prime factorization are (2), (4), (6), (4, 2), (8), (6, 2), (4, 4). The sums of each of these exponents per term is <= 8. There are 10 exponents listed. Of these 10 there are 5 of them divisible by 4. Therefore R(8) = 5/10.

Then it seems that R(n) tends to some value > 0.8 as n grows. (End)

Discussion
Mon Dec 30
18:11
David A. Corneth: I put the comma and tried to quantify the divisible by 4 thingy. Is that okay?