Alan Griffiths has authored 2 sequences.
A211133
Odd sides belonging to multiple primitive Euler bricks.
Original entry on oeis.org
1155, 4599, 5643, 8415, 9405, 10395, 10725, 66495, 200385, 1100385, 1769229, 2518725, 2673585, 2807805, 4150575, 4362115, 8191161, 8954495, 11534489, 12645009, 13435565, 19875933, 25560909, 31122325, 45285075, 45930885, 55257111, 62379225, 75081435, 93205889
Offset: 1
A133155
Numbers formed by setting bits representing odd primes, where bit_no = (prime - 1)/2. Setting bit number b is the same as OR-ing with 2^b (i.e., bit numbers start at zero).
Original entry on oeis.org
2, 6, 14, 46, 110, 366, 878, 2926, 19310, 52078, 314222, 1362798, 3459950, 11848558, 78957422, 615828334, 1689570158, 10279504750, 44639243118, 113358719854, 663114533742, 2862137789294, 20454323833710, 301929300544366, 1427829207386990, 3679629021072238
Offset: 1
a(3) = 14 because 3, 5 and 7 are odd primes so therefore bits 1, 2 and 3 are set and bit zero is not. 1110_2 = 14.
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import gmpy
a = gmpy.mpz(0)
i = 0
for p in range(3,100,2):
if gmpy.is_prime(p):
a = gmpy.setbit(a,(p-1)/2)
i += 1
print(i,a)
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