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A338398
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Inverse boustrophedon transform of the primes.
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1
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2, 1, 1, -3, -1, -29, 33, -315, 1251, -7905, 48667, -344723, 2623549, -21739937, 193680399, -1849767375, 18840708855, -203907377005, 2336594492591, -28262970918841, 359855118160333, -4810909461068941, 67379837645787507, -986592769520379701
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OFFSET
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0,1
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LINKS
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FORMULA
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a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(n,k) * A000111(n-k) * A000040(k+1).
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PROG
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(Python)
import sympy
T=[]
for k in range(n+1):
T.append(sympy.prime(k+1))
T.reverse()
for i in range(k):
T[i+1]=T[i]-T[i+1]
return T[-1]
(Python)
from itertools import accumulate, islice, count
from operator import sub
from sympy import prime
def A338398_gen(): # generator of terms
blist = tuple()
for i in count(1):
yield (blist := tuple(accumulate(reversed(blist), func=sub, initial=prime(i))))[-1]
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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