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A353731
a(n) = index where prime(n) appears in A352808.
3
2, 6, 4, 11, 18, 19, 16, 24, 45, 52, 63, 29, 30, 78, 122, 71, 123, 148, 46, 72, 53, 162, 96, 66, 100, 161, 243, 212, 194, 186, 394, 75, 86, 110, 114, 177, 204, 111, 254, 295, 273, 274, 494, 124, 167, 386, 338, 642, 339, 410, 347, 650, 351, 762, 159, 180, 195, 250, 191, 208, 225, 270, 284, 595, 340, 689, 290, 238, 732, 730, 258, 651, 696, 624, 749, 1062, 271, 311, 300, 326, 666, 625, 1006, 634, 1007, 1050, 269, 738, 759, 970, 898, 1443, 1122, 1123, 1139, 1570, 1483
OFFSET
1,1
COMMENTS
Here prime(n) means the n-th prime in 2, 3, 5, 7, ..., not the n-th term of A352808 that happens to be a prime.
LINKS
FORMULA
a(n) = k if A352808(k) = prime(n). - Michael S. Branicky, May 17 2022
PROG
(Python)
from sympy import nextprime
from itertools import count, islice
def agen(): # generator of terms
A352808lst = [0, 1]; A352808set = {0, 1}
mink = p = 2
for n in count(2):
ahalf, k = A352808lst[n//2], mink
while k in A352808set or k&ahalf: k += 1
A352808lst.append(k); A352808set.add(k)
while mink in A352808set: mink += 1
while p in A352808set: yield A352808lst.index(p); p = nextprime(p)
print(list(islice(agen(), 76))) # Michael S. Branicky, May 17 2022
CROSSREFS
Sequence in context: A371285 A090546 A242901 * A266013 A222423 A059909
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, May 17 2022
STATUS
approved