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A373338
Characteristic function of A333242: a(n) = 1 if n is a term of A333242.
2
0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0
OFFSET
1,1
COMMENTS
This sequence is the result of applying the N-sieve to generate the prime number subsequence A333242 where 1 indicates a prime number chosen to be included in sequence A333242 and 0 indicates the prime numbers and composites not in A333242.
FORMULA
a(n) = A078442(n) mod 2
MATHEMATICA
Select[Prime@ Range@ 75, EvenQ@ Length@ NestWhileList[ PrimePi, #, PrimeQ] &]
PROG
(PARI) A078442(n) = my(k=0); while(isprime(n), k++; n=primepi(n)); k;
a(n) = A078442(n) % 2; \\ Michel Marcus, Jun 15 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael P. May, Jun 01 2024
STATUS
approved