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A239580 Numbers n such that A227364(n) = 1 + 2*3 + 4*5*6 + 7*8*9*10 + ... + ...*n  is a prime. 0
2, 3, 4, 6, 9, 10, 13, 14, 15, 18, 30, 32, 54, 58, 59, 81, 85, 128, 140, 203, 204, 206, 209, 223, 286, 305, 343, 350, 367, 397, 399, 451, 453, 506, 534, 656, 676, 698, 730, 756, 845, 849, 878, 944, 1020, 1040, 1091, 1248, 1256, 1300, 1310, 1326, 1364, 1406, 1535 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..55.

PROG

(Python)

import sympy

from sympy import isprime

for n in range(10000):

  sum = 0

  i = k = 1

  while i<=n:

    product = 1

    for x in range(k):

      product *= i

      i += 1

      if i>n: break

    sum += product

    k += 1

  if isprime(sum):  print str(n)+', ',

CROSSREFS

Cf. A227364.

Sequence in context: A128399 A051404 A046097 * A175515 A241241 A260343

Adjacent sequences:  A239577 A239578 A239579 * A239581 A239582 A239583

KEYWORD

nonn

AUTHOR

Alex Ratushnyak, Mar 21 2014

STATUS

approved

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Last modified February 19 13:20 EST 2020. Contains 332044 sequences. (Running on oeis4.)