[[66]] is not prime. Want proof? :)

[[66]] is composite: 2 * 33.

[[66]] is composite: 3 * 22.

Primes up to 66: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61.

hex(1) is 1.

hex(2) is 7.

hex(3) is 19.

hex(4) is 37.

hex(5) is 61.

hex(6) is 91.

hex(7) is 127.

hex(8) is 169.

hex(9) is 217.

hex(10) is 271.

hex(11) is 331.

hex(12) is 397.

hex(13) is 469.

hex(14) is 547.

hex(15) is 631.

hex(16) is 721.

hex(17) is 817.

hex(18) is 919.

hex(19) is 1027.

hex(20) is 1141.

hex(21) is 1261.

hex(22) is 1387.

hex(23) is 1519.

hex(24) is 1657.

hex(25) is 1801.

hex(26) is 1951.

hex(27) is 2107.

hex(28) is 2269.

hex(29) is 2437.

hex(30) is 2611.

hex(31) is 2791.

hex(32) is 2977.

hex(33) is 3169.

hex(34) is 3367.

hex(35) is 3571.

hex(36) is 3781.

hex(37) is 3997.

hex(38) is 4219.

hex(39) is 4447.

hex(40) is 4681.

hex(41) is 4921.

hex(42) is 5167.

hex(43) is 5419.

hex(44) is 5677.

hex(45) is 5941.

hex(46) is 6211.

hex(47) is 6487.

hex(48) is 6769.

hex(49) is 7057.

hex(50) is 7351.

hex(51) is 7651.

hex(52) is 7957.

hex(53) is 8269.

hex(54) is 8587.

hex(55) is 8911.

hex(56) is 9241.

hex(57) is 9577.

hex(58) is 9919.

hex(59) is 10267.

hex(60) is 10621.

hex(61) is 10981.

hex(62) is 11347.

hex(63) is 11719.

hex(64) is 12097.

hex(65) is 12481.

hex(66) is 12871.

• [[square]]: 4356

• [[square root]]: 8.1240

• [[cube]]: 287496

• [[cube root]]: 4.0412

• [[natural log]] (ln): 4.1897

• [[base-10 log]] (log10): 1.8195

• [[base-2 log]] (log2): 6.0444