1,1

This is not an arbitrary thing to do, as in some cases the spradic group has an order depending on a specific power, as with A001228(1) + 1 = 7921 = 89^2 and A001228(3) + 1 = 175561 = 419^2. The largest integer to check is the 1 + the order of ther monster group, which is the semiprime 808017424794512875886459904961710757 005754368000 000001 = 18250906752127213 * 44272727693397225537389001926419 074277.

({A001228(n) + 1} UNION {A001228(n) - 1}) INTERSECTION A000040.

a(1) = 7919 = A001228(1) - 1.

a(2) = 604801 = A001228(5) + 1.

a(3) = 10200959 = A001228(6) - 1.

a(4) = 44351999 = A001228(7) - 1.

a(5) = 44352001 = A001228(7) + 1.

a(6) = 50232961 = A001228(8) + 1.

a(7) = 244823041 = A001228(9) + 1.

a(8) = 460815505919 = A001228(14) + 1.

a(9) = 64561751654399 = A001228(17) - 1.

a(10) = 4089470473293004801 = A001228(21) + 1.

a(11) = 4157776806543360001 = A001228(22) + 1.

a(12) = 86775571046077562879 = A001228(23) - 1.

Cf. A000040, A001228.

Sequence in context: A115426 A155178 A031922 this_sequence A001228 A036325 A031677

Adjacent sequences: A121233 A121234 A121235 this_sequence A121237 A121238 A121239

easy,fini,full,nonn

Jonathan Vos Post (jvospost3(AT)gmail.com), Aug 21 2006