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A100016 revision #17

A100016
a(0) = 1; a(n+1) = a(n) * (next prime larger than a(n)).
2
1, 2, 6, 42, 1806, 3270666, 10697259354222, 114431357691543566765996394, 13094535623129987017538646614449662873664453962869814, 171466863185420237392391564368967506501628543653753176958938044126997508808439363294403869833497610468982
OFFSET
0,2
COMMENTS
Terms are very close to A007018(n), with equality for the first 5 terms. Indeed, sequence A007018 is defined like the present sequence, with nextprime(a(n)) replaced by a(n)+1. - M. F. Hasler, May 20 2019
EXAMPLE
If n=1, then the prime immediately greater than n is 2. Hence the next number is n*p = 1*2 = 2.
If n=2, then the next prime is 3, so the next number in the sequence is 2*3=6.
If n=6, then the next prime is 7, so the next number in the sequence is 6*7=42.
MATHEMATICA
a[0] = 1; a[n_] := a[n - 1]*NextPrime[a[n - 1]]; Table[ a[n], {n, 0, 9}] (* Robert G. Wilson v, Nov 23 2004 *)
NestList[# NextPrime[#]&, 1, 10] (* Harvey P. Dale, Oct 15 2016 *)
PROG
(PARI) (nxt_A100016(n)=n*nextprime(n+1)); A100016_vec=vector(10, i, t=if(i>1, nxt_A100016(t), 1)) \\ M. F. Hasler, May 20 2019
(Python)
from itertools import islice
from sympy import nextprime
def A100016_gen(): # generator of terms
yield (a:=1)
while (a:=a*nextprime(a)): yield a
A100016_list = list(islice(A100016_gen(), 10)) # Chai Wah Wu, Mar 19 2024
CROSSREFS
Similar to A074839.
Even more similar to A007018.
Sequence in context: A230311 A276416 A007018 * A344562 A000610 A023363
KEYWORD
nonn
AUTHOR
Parthasarathy Nambi, Nov 18 2004
EXTENSIONS
More terms from Robert G. Wilson v, Nov 23 2004
STATUS
reviewed