A186075 Irregular triangle, read by rows, of primes with suffix n and digits "9" prepended, otherwise 0.

0, 0, 0, 0, 0, 0, 97, 997, 0, 0, 0, 911, 0, 0, 0, 0, 0, 0, 0, 919, 0, 0, 0, 0, 0, 0, 0, 0, 0, 929, 9929, 99929, 0, 0, 0, 0, 0, 0, 0, 937, 0, 0, 0, 941, 9941, 0, 0, 0, 0, 0, 947, 0, 0, 0, 0, 0, 953, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 967, 9967, 0, 0, 0, 971, 0, 0, 0, 0, 0, 977

Offset

1,7

Comments

Row n ends when a composite number is found. ~

Links

Table of n, a(n) for n=1..82.

Example

for k=1..3 , a(29, k) = {929, 9929,99929} are in the sequence.

Maple

with(numtheory): for n from 1 to 100 do:a0:=n:id:=0:c:=0:for k from 1 to 20
  while (id=0) do:d:=length(a0):a1:=9*10^d+a0:if type(a1, prime)=true then a0:=a1:printf(`%d,
  `, a0):c:=c+1:else id:=1:fi:od:if c=0 then printf(`%d, `, 0):else fi:od:

Crossrefs

Cf. A186071 A186072 A186073 A185682 A185684 A185685 A185687.

Sequence in context: A093944 A127748 A127828 * A087596 A133836 A224106

Adjacent sequences: A186072 A186073 A186074 * A186076 A186077 A186078

Keyword

nonn,base,tabf

Author

Michel Lagneau, Feb 11 2011

Status

approved