A129734 List of primitive prime divisors of the numbers 3^n-2^n (A001047) in their order of occurrence.

5, 19, 13, 211, 7, 29, 71, 97, 1009, 11, 23, 331, 61, 53, 29927, 463, 3571, 17, 401, 129009091, 577, 1559, 745181, 4621, 43, 6217, 35839, 47, 2002867877, 5521, 101, 39756701, 79, 4057, 397760329, 369181, 68629840493971, 31, 241, 617671248800299, 3041, 14177

Offset: 1

Author

N. J. A. Sloane, May 13 2007

Keywords

• nonn

Comments

Read A001047 term-by-term, factorize each term, write down any primes not seen before.

Links

• Amiram Eldar, Table of n, a(n) for n = 1..1893
• Graham Everest, Shaun Stevens, Duncan Tamsett and Tom Ward, Primes generated by recurrence sequences, Amer. Math. Monthly, 114 (No. 5, 2007), 417-431.
• K. Zsigmondy, Zur Theorie der Potenzreste, Monatsh. Math., 3 (1892), 265-284.

Crossrefs

Cf. A001047, A058765, A057468; A003462, A076481, A028491, A129733; A000225, A004668, A000043, A108974.

Extensions

a(41) and a(42) switched by Amiram Eldar, Jun 30 2023