A202286 -id:A202286 - cp's OEIS frontend

A209063 Let p = A099180(n) be the n-th prime which is greater than its reversal p'; a(n) = number of ways to write p as a multiple of p' +- q where q is a prime < p.

1, 2, 0, 1, 4, 3, 0, 2, 1, 1, 1, 1, 1, 1, 0, 0, 3, 2, 4, 0, 0, 2, 0, 2, 1, 3, 1, 1, 1, 1, 1, 4, 1, 4, 2, 0, 1, 2, 1, 1, 1, 2, 1, 0, 1, 1, 1, 4, 4, 1, 0, 1, 1, 2, 0, 3, 2, 0, 0, 3, 1, 3, 0, 0, 1, 3, 0, 0, 2, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1

Offset: 1

N. J. A. Sloane, Mar 13 2012

Sequence is bounded - see A202286.

			For n=6, p = 71, p' = 17 and there are three solutions:
71 = 2*17 + 3771 = 4*17 + 371 = 6*17 - 31, so a(6) = 3.

Cf. A099180, A209914. A202286 gives smallest m such that a(m) = n.

A209063(n)=A209914(A099180(n)) \\ M. F. Hasler, Mar 15 2012

Equals A209914 o A099180. - M. F. Hasler, Mar 15 2012

A099180 Primes p which are greater than p reversed.

Original entry on oeis.org

31, 41, 43, 53, 61, 71, 73, 83, 97, 211, 241, 251, 271, 281, 311, 331, 401, 421, 431, 433, 443, 461, 463, 491, 503, 521, 523, 541, 563, 571, 593, 601, 613, 631, 641, 643, 653, 661, 673, 683, 691, 701, 733, 743, 751, 761, 773, 811, 821, 823, 827, 853, 857, 863

Offset: 1

Robert G. Wilson v, Oct 01 2004

Cf. A209063, A202286.

Select[ Prime[ Range[ 150]], # > FromDigits[ Reverse[ IntegerDigits[ # ]]] &]

A099180(n)=type(A99180)=="t_VEC" || A99180=[31]; #A99180>=n && return(A99180[n]); my(p=A99180[#A99180]); A99180=concat(A99180, vector(n-#A99180, k, until(A004086(p=nextprime(p+1))M. F. Hasler, Mar 15 2012

A99180=select( p->A004086(p)M. F. Hasler, Mar 15 2012

A182239 Primes equal to a multiple of its reversal +/- a prime smaller than itself in exactly 8 ways.

Original entry on oeis.org

845534401, 83565065201, 829144019201, 834854554601, 854516148301, 866422665701, 878554044001, 889419071111, 890750408711, 891079866601

Offset: 1

Hans Havermann, Apr 20 2012

Hans Havermann, Eight

Cf. A202286, A209063.

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A209063 Let p = A099180(n) be the n-th prime which is greater than its reversal p'; a(n) = number of ways to write p as a multiple of p' +- q where q is a prime < p.

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A099180 Primes p which are greater than p reversed.

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A182239 Primes equal to a multiple of its reversal +/- a prime smaller than itself in exactly 8 ways.

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