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A202114
Numbers n such that 90n + 53 is prime.
3
0, 2, 5, 6, 7, 8, 9, 10, 13, 16, 17, 24, 26, 29, 30, 31, 33, 35, 42, 43, 44, 47, 48, 49, 51, 52, 55, 58, 64, 65, 68, 69, 70, 75, 77, 80, 82, 83, 85, 86, 87, 91, 93, 94, 96, 97, 99, 103, 104, 112, 113, 114, 120, 124, 126, 127, 132, 134, 135, 138, 140, 141
OFFSET
1,2
COMMENTS
This sequence was generated by adding 12 Fibonacci-like sequences [See: PROG]. Looking at the format 90n+53 modulo 9 and modulo 10 we see that all entries of A142316 have digital root 8 and last digit 3. (Reverting the process is an application of the Chinese remainder theorem.) The 12 Fibonacci-like sequences are generated (via the p and q "seed" values entered into the PERL program) from the base p,q pairs 53*91, 19*17, 37*89, 73*71, 11*13, 29*67, 47*49, 83*31, 23*61, 41*43, 59*7, 77*79.
MATHEMATICA
Select[Range[0, 200], PrimeQ[90 # + 53] &]
PROG
(PARI) is(n)=isprime(90*n+53) \\ Charles R Greathouse IV, Feb 20 2017
KEYWORD
nonn,easy
AUTHOR
J. W. Helkenberg, Dec 11 2011
STATUS
approved