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A353630
Arithmetic derivative of primorial base exp-function, reduced modulo 4.
9
0, 1, 1, 1, 2, 1, 1, 3, 0, 3, 3, 3, 2, 1, 3, 1, 0, 1, 3, 3, 2, 3, 1, 3, 0, 1, 1, 1, 2, 1, 1, 1, 2, 1, 3, 1, 0, 3, 3, 3, 2, 3, 3, 1, 0, 1, 1, 1, 2, 3, 1, 3, 0, 3, 1, 1, 2, 1, 3, 1, 2, 1, 3, 1, 0, 1, 3, 3, 2, 3, 1, 3, 0, 1, 1, 1, 2, 1, 1, 3, 0, 3, 3, 3, 2, 1, 3, 1, 0, 1, 3, 1, 0, 1, 1, 1, 2, 3, 1, 3, 0, 3, 1, 1, 2, 1
OFFSET
0,5
FORMULA
a(n) = A010873(A327860(n)).
a(n) = A353493(A276086(n)).
a(n) = A010873(A328572(n)*A353640(n)). [Note that all terms of A328572 are odd]
PROG
(PARI) A353630(n) = { my(s=0, m=1, p=2, e); while(n, e = (n%p); m *= (p^e); s += (e/p); n = n\p; p = nextprime(1+p)); ((s*m)%4); };
CROSSREFS
Cf. A010873, A166486 (parity of terms), A276086, A327860, A328572, A353493, A353640.
Cf. A353631, A353632 (bisections).
Cf. also A353486.
Sequence in context: A033804 A103910 A155993 * A341091 A210806 A147867
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, May 01 2022
STATUS
approved