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Convolution of primes with odd primes.
3

%I #23 Sep 08 2022 08:46:01

%S 6,19,44,89,162,271,424,633,910,1275,1732,2309,3018,3859,4872,6057,

%T 7446,9051,10888,12997,15358,18011,20972,24277,27950,31991,36464,

%U 41325,46602,52367,58612,65385,72722,80651,89160,98317,108070,118535,129756,141713,154442

%N Convolution of primes with odd primes.

%H Reinhard Zumkeller, <a href="/A209403/b209403.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = Sum_{k=1..n} A000040(k) * A065091(n-k+1).

%e a(2) = 2*5 + 3*3 = 19.

%t Rest[Flatten[Table[ListConvolve[Prime[Range[2,n]],Prime[Range[n-1]]],{n,50}]]] (* _Harvey P. Dale_, Jan 10 2022 *)

%o (Haskell)

%o a209403 n = sum $

%o zipWith (*) (reverse $ take n a000040_list) a065091_list

%o (Magma) [&+[NthPrime(k)*NthPrime(n+1-k): k in [1..n-1]]: n in [2..40]]; // _Bruno Berselli_, Mar 08 2012

%o (Python)

%o from numpy import convolve

%o from sympy import prime, primerange

%o def aupton(nn):

%o primes = list(primerange(2, prime(nn+1)+1))

%o return list(convolve(primes[:-1], primes[1:]))[:nn]

%o print(aupton(41)) # _Michael S. Branicky_, Jun 19 2021

%Y Cf. A000040, A065091, A014342.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Mar 08 2012