proposed

approved

editing

proposed

Cf. A000720, A332806, A108549 (fixed points), A332818, A332819.

A332806list(up_to) = { my(v=vector(2), xs=Map(), lista=List([]), p, q, u); v[2] = 3; v[1] = 5; mapput(xs, 1, 1); mapput(xs, 2, 2); mapput(xs, 3, 3); for(n=4, up_to, p = v[2-(n%2)]; q = nextprime(1+p); while(q%4 != p%4, q=nextprime(1+q)); v[2-(n%2)] = q; mapput(xs, primepi(q), n)); for(i=1, oo, if(!mapisdefined(xs, i, &u), return(Vec(lista)), listput(lista, prime(u)))); };

Antti Karttunen, <a href="/A332808/b332808.txt">Table of n, a(n) for n = 1..26927</a>

Cf. A000720, A332806, A108549 (fixed points).

Differs from its inverse Inverse permutation is A108548 , from which this differs for the first time at n=67, where a(67) = 71, while A108548(67) = 73.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 13, 12, 11, 14, 15, 16, 17, 18, 19, 20, 21, 26, 29, 24, 25, 22, 27, 28, 23, 30, 37, 32, 39, 34, 35, 36, 31, 38, 33, 40, 41, 42, 43, 52, 45, 58, 53, 48, 49, 50, 51, 44, 47, 54, 65, 56, 57, 46, 61, 60, 59, 74, 63, 64, 55, 78, 71, 68, 87, 70, 79, 72, 67, 62, 75, 76, 91, 66, 89, 80, 81, 82, 101

1,12

allocated for Antti KarttunenFully multiplicative with a(p) = A332806(A000720(p)).

5, 6, 7, 8, 9, 10, 13, 12, 11, 14, 15, 16, 17, 18, 19, 20, 21, 26, 29, 24, 25, 22, 27, 28, 23, 30, 37, 32, 39, 34, 35, 36, 31, 38, 33, 40, 41, 42, 43, 52, 45, 58, 53, 48, 49, 50, 51, 44, 47, 54, 65, 56, 57, 46, 61, 60, 59, 74, 63, 64, 55, 78, 71, 68, 87, 70, 79, 72, 67, 62, 75

1,1

(PARI)

up_to = 10000;

A332806list(up_to) = { my(v=vector(2), xs=Map(), lista=List([]), p, q); v[2] = 3; v[1] = 5; mapput(xs, 1, 1); mapput(xs, 2, 2); mapput(xs, 3, 3); for(n=4, up_to, p = v[2-(n%2)]; q = nextprime(1+p); while(q%4 != p%4, q=nextprime(1+q)); v[2-(n%2)] = q; mapput(xs, primepi(q), n)); for(i=1, oo, if(!mapisdefined(xs, i, &u), return(Vec(lista)), listput(lista, prime(u)))); };

v332806 = A332806list(up_to);

A332806(n) = v332806[n];

A332808(n) = { my(f=factor(n)); f[, 1] = apply(A332806, apply(primepi, f[, 1])); factorback(f); };

Cf. A000720, A332806.

Differs from its inverse A108548 for the first time at n=67, where a(67) = 71, while A108548(67) = 73.

allocated

nonn,mult

Antti Karttunen, Feb 27 2020

approved

editing

allocated for Antti Karttunen

allocated

approved