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A330688 Record values in A050377, number of ways to factor n into "Fermi-Dirac primes" (A050376). 3
1, 2, 4, 6, 8, 10, 12, 14, 16, 20, 24, 28, 40, 56, 60, 80, 84, 104, 112, 120, 144, 160, 168, 184, 200, 208, 216, 224, 240, 260, 288, 320, 360, 368, 400, 416, 432, 460, 480, 520, 576, 600, 624, 640, 720, 736, 800, 864, 920, 960, 1040, 1104, 1120, 1152, 1200, 1440, 1456, 1472, 1480, 1600, 1840, 2016, 2080, 2400, 2576, 2880, 2960, 3360 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = A050377(A330687(n)).
PROG
(PARI)
upto_e = 101; \\ 101 --> 211 terms
A018819(n) = if( n<1, n==0, if( n%2, A018819(n-1), A018819(n/2)+A018819(n-1))); \\ From A018819
v018819 = vector(upto_e, n, A018819(n));
A050377(n) = factorback(apply(e -> v018819[e], factor(n)[, 2]));
A283980(n) = {my(f=factor(n)); prod(i=1, #f~, my(p=f[i, 1], e=f[i, 2]); if(p==2, 6, nextprime(p+1))^e)}; \\ From A283980
A330688list(e) = { my(lista = List([1, 2]), i=2, u = 2^e, t, m=0, v025487); while(lista[i] != u, if(2*lista[i] <= u, listput(lista, 2*lista[i]); t = A283980(lista[i]); if(t <= u, listput(lista, t))); i++); v025487 = vecsort(Vec(lista)); lista = List([]); for(i=1, #v025487, if((t=A050377(v025487[i]))>m, listput(lista, t); m=t)); Vec(lista); };
v330688 = A330688list(upto_e);
A330688(n) = v330688[n];
CROSSREFS
Sequence in context: A363488 A118081 A152483 * A280743 A162764 A082893
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 28 2019
STATUS
approved

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Last modified April 15 05:45 EDT 2024. Contains 371667 sequences. (Running on oeis4.)