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A096280 Primes in A007443 (= binomial transform of primes). 1
2, 5, 13, 83, 2707, 71475193, 674721797, 6245693407, 118543624847, 82736199371081, 72298621492552303967009812018997, 2454725173623452943975951834280921, 59966692897276736774965300014477948187539553 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Sum of reciprocals = 0.2893406979695919267175673140... Are these primes infinite?
The next term is too large to be displayed here. See A287915 for the indices k which yield these primes A007443(k). - M. F. Hasler, Jun 02 2017
LINKS
Paolo Xausa, Table of n, a(n) for n = 1..20 (terms 1..17 from M. F. Hasler)
FORMULA
a(n) = A007443(A287915(n)). - M. F. Hasler, Jun 02 2017
MATHEMATICA
A007443[n_]:=Sum[Binomial[n-1, k-1]Prime[k], {k, n}];
With[{upto=500}, Select[Array[A007443, upto], PrimeQ]] (* or *)
Module[{upto=500, b}, b=Prime[Range[upto]]; Join[{2}, Select[Table[First[b=ListConvolve[{1, 1}, b]], upto-1], PrimeQ]]] (* Paolo Xausa, Oct 31 2023 *)
PROG
(PARI) \\ n = terms to add, m = order.
sucsumspr(n, m) = { local(a, b, i, j, k, sr); sr=0; a = primes(1001); b = vector(1001); for(i=1, m, for(j=1, n+n, b[j] = a[j]+ a[j+1]; ); a=b; if(isprime(a[1]), print1(a[1]", "); sr+=1.0/a[1]); ); print(); print(sr); }
(PARI) for(n=1, 999, ispseudoprime(A007443(n))&&print1(A007443(n)", ")) \\ M. F. Hasler, Jun 02 2017
CROSSREFS
See A287915 for the corresponding indices of A007443.
Sequence in context: A081650 A092262 A365326 * A236395 A032015 A325626
KEYWORD
nonn
AUTHOR
Cino Hilliard, Jun 23 2004
EXTENSIONS
Definition corrected, initial term 2 added, and edited by M. F. Hasler, Jun 02 2017
Name simplified by Paolo Xausa, Nov 05 2023
STATUS
approved

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Last modified April 19 03:57 EDT 2024. Contains 371782 sequences. (Running on oeis4.)