A342604 -id:A342604 - cp's OEIS frontend

A342605 Numbers k such that A342604(k) is prime.

1, 2, 4, 14, 20, 26, 31, 39, 42, 57, 64, 69, 87, 92, 114, 127, 150, 152, 172, 213, 274, 301, 326, 379, 436, 460, 499, 523, 597, 708, 747, 817, 819, 912, 1382, 1452, 1595, 1600, 1603, 1632, 1647, 1670, 1768, 1833, 1834, 1873, 1890, 1986, 2137, 2696, 2702, 2859, 3080, 3154, 3167, 3173, 3386, 3933

Offset: 1

J. M. Bergot and Robert Israel, Mar 16 2021

nonn

			a(3) = 4 is a term because A342604(4) = 17 is prime.

Robert Israel, Table of n, a(n) for n = 1..1000

Cf. A342604, A342606.

p:= 1: R:= NULL:
for n from 0 to 14 do
  for k from 0 to n do
    p:= nextprime(p);
    R:= R, binomial(n,k)*p
od od:
S:= ListTools:-PartialSums([R]):
select(t -> isprime(S[t]), [$1..nops(S)]);

A342604(a(n)) = A342606(n).

A342606 Primes in A342604.

Original entry on oeis.org

2, 5, 17, 821, 2851, 8291, 12583, 32213, 64567, 193283, 481409, 507979, 2889443, 3026911, 15233891, 24430993, 95635361, 95754697, 221519339, 1147397567, 12921783863, 28711457651, 63521027291, 305580335353, 1449155675287, 3157505489581, 6839699592347, 14717764856273, 67875393766057

Offset: 1

J. M. Bergot and Robert Israel, Mar 16 2021

nonn

Robert Israel, Table of n, a(n) for n = 1..741

Cf. A342604, A342605.

p:= 1: R:= NULL:
for n from 0 to 14 do
  for k from 0 to n do
    p:= nextprime(p);
    R:= R, binomial(n, k)*p
od od:
select(isprime,ListTools:-PartialSums([R]));

a(n) = A342604(A342605(n)).

cp's OEIS Frontend

A342605 Numbers k such that A342604(k) is prime.

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