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A108510 Primes p such that 3^A000027*(7*p) is a subsequence of A033631. 1
1979, 2699, 7649, 1131569, 2482199, 2886839, 90425537, 2774476799 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
There is no further term up to prime(300000000).
LINKS
EXAMPLE
Let n be a natural number and m=3^n*7*90425537;
then sigma(phi(m)) = sigma(3^(n-1)*2*6*90425536) = sigma(3^n*2^8*677*2087) = sigma(3^n)*8*90425538 = sigma(3^n)*sigma(7)*sigma(90425537) = sigma(3^n*7*90425537) = sigma(m),
hence m is in A033631 and the prime number 90425537 is a term of this sequence.
CROSSREFS
Sequence in context: A205364 A210160 A234179 * A343971 A343972 A225235
KEYWORD
more,nonn
AUTHOR
Farideh Firoozbakht, Jun 07 2005
STATUS
approved

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Last modified March 2 21:08 EST 2024. Contains 370498 sequences. (Running on oeis4.)