

A202129


Numbers n such that 90n + 71 is prime.


1



0, 2, 4, 5, 7, 9, 10, 11, 12, 16, 17, 20, 23, 26, 28, 31, 33, 35, 38, 39, 40, 41, 42, 46, 48, 49, 52, 54, 55, 59, 60, 62, 63, 66, 67, 72, 76, 77, 82, 83, 87, 89, 90, 101, 103, 104, 105, 108, 111, 112, 114, 117, 118, 119, 125, 126, 129, 133, 137, 138, 140
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OFFSET

1,2


COMMENTS

This sequence was generated by adding 12 Fibonaccilike sequences [See: PROG?]. Looking at the format 90n+71 modulo 9 and modulo 10 we see that all entries of A142325 have digital root 8 and last digit 1. (Reverting the process is an application of the Chinese remainder theorem.) The 12 Fibonaccilike sequences are generated (via the p and q "seed" values entered into the Perl program) from the base p,q pairs 71*91, 19*89, 37*53, 73*13, 11*31, 29*49, 47*13, 83*67, 23*7, 41*61, 59*79, 77*43.


LINKS

Table of n, a(n) for n=1..61.


MATHEMATICA

Select[Range[0, 200], PrimeQ[90 # + 71] &]


PROG

(PARI) is(n)=isprime(90*n+71) \\ Charles R Greathouse IV, Jun 13 2017


CROSSREFS

Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104, A202105, A202110, A202112, A202113, A202114, A202115, A202116.
Sequence in context: A217378 A140204 A084577 * A288217 A026457 A185598
Adjacent sequences: A202126 A202127 A202128 * A202130 A202131 A202132


KEYWORD

nonn,easy


AUTHOR

J. W. Helkenberg, Dec 11 2011


STATUS

approved



