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A370607
2-valuations of terms of A370606.
2
0, 1, 2, 4, 5, 6, 8, 9, 12, 13, 16, 18, 19, 20, 21, 22, 25, 26, 27, 30, 31, 33, 36, 37, 39, 41, 42, 43, 44, 45, 46, 47, 48, 50, 52, 55, 56, 57, 59, 60, 63, 66, 67, 68, 69, 70, 71, 75, 77, 78, 81, 82, 85, 86, 87, 88, 89, 92, 93, 94, 95, 96, 98, 99, 100, 103, 104
OFFSET
1,3
PROG
(PARI) r=-1; forprime(p=2, 10^12, v=valuation(p-1, 2); if(v>r, print1(v, ", "); r=v));
(Python)
from itertools import count, islice
from sympy import isprime
def A370607_gen(): # generator of terms
a = 1
while True:
for q in count(a, a):
if isprime(q+1):
yield (b:=q&-q).bit_length()-1
a = b<<1
break
A370607_list = list(islice(A370607_gen(), 30)) # Chai Wah Wu, Feb 23 2024
CROSSREFS
Sequence in context: A048262 A333489 A345167 * A285035 A374698 A233564
KEYWORD
nonn
AUTHOR
Joerg Arndt, Feb 23 2024
EXTENSIONS
a(21)-a(67) from Chai Wah Wu, Feb 23 2024
STATUS
approved