A073221
The terms of A073213 (sums of two powers of 17) divided by 2.
Original entry on oeis.org
1, 9, 17, 145, 153, 289, 2457, 2465, 2601, 4913, 41761, 41769, 41905, 44217, 83521, 709929, 709937, 710073, 712385, 751689, 1419857, 12068785, 12068793, 12068929, 12071241, 12110545, 12778713, 24137569, 205169337, 205169345, 205169481, 205171793, 205211097, 205879265, 217238121, 410338673
Offset: 0
a(4) = 145 = (17^2+17^0) / 2.
A073211
Sum of two powers of 11.
Original entry on oeis.org
2, 12, 22, 122, 132, 242, 1332, 1342, 1452, 2662, 14642, 14652, 14762, 15972, 29282, 161052, 161062, 161172, 162382, 175692, 322102, 1771562, 1771572, 1771682, 1772892, 1786202, 1932612, 3543122, 19487172, 19487182, 19487292, 19488502, 19501812, 19648222, 21258732, 38974342
Offset: 0
T(2,0) = 11^2 + 11^0 = 122.
Table T(n,m) begins:
2;
12, 22;
122, 132, 242;
1332, 1342, 1452, 2662;
14642, 14652, 14762, 15972, 29282;
...
Sums of two powers of n:
A073423 (0),
A007395 (1),
A173786 (2),
A055235 (3),
A055236 (4),
A055237 (5),
A055257 (6),
A055258 (7),
A055259 (8),
A055260 (9),
A052216 (10),
A194887 (12),
A072390 (13),
A055261 (16),
A073213 (17),
A073214 (19),
A073215 (23).
-
t = 11^Range[0, 9]; Select[Union[Flatten[Table[i + j, {i, t}, {j, t}]]], # <= t[[-1]] + 1 &] (* T. D. Noe, Oct 09 2011 *)
-
from math import isqrt
def A073211(n): return 11**(a:=(k:=isqrt(m:=n<<1))+(m>k*(k+1))-1)+11**(n-1-(a*(a+1)>>1)) # Chai Wah Wu, Apr 09 2025
A073214
Sum of two powers of 19.
Original entry on oeis.org
2, 20, 38, 362, 380, 722, 6860, 6878, 7220, 13718, 130322, 130340, 130682, 137180, 260642, 2476100, 2476118, 2476460, 2482958, 2606420, 4952198, 47045882, 47045900, 47046242, 47052740, 47176202, 49521980, 94091762, 893871740, 893871758, 893872100, 893878598, 894002060, 896347838, 940917620, 1787743478
Offset: 0
T(2,0) = 19^2 + 19^0 = 362.
Table begins:
2;
20, 38;
362, 380, 722;
6860, 6878, 7220, 13718;
130322, 130340, 130682, 137180, 260642;
...
Sums of two powers of n:
A073423 (0),
A007395 (1),
A173786 (2),
A055235 (3),
A055236 (4),
A055237 (5),
A055257 (6),
A055258 (7),
A055259 (8),
A055260 (9),
A052216 (10),
A073211 (11),
A194887 (12),
A072390 (13),
A055261 (16),
A073213 (17),
A073215 (23).
-
Flatten[Table[Table[19^n + 19^m, {m, 0, n}], {n, 0, 7}]] (* T. D. Noe, Jun 18 2013 *)
Total/@Tuples[19^Range[0,10],2]//Union (* Harvey P. Dale, Jan 04 2019 *)
-
from math import isqrt
def A073214(n): return 19**(a:=(k:=isqrt(m:=n<<1))+(m>k*(k+1))-1)+19**(n-1-(a*(a+1)>>1)) # Chai Wah Wu, Apr 09 2025
A073215
Sum of two powers of 23.
Original entry on oeis.org
2, 24, 46, 530, 552, 1058, 12168, 12190, 12696, 24334, 279842, 279864, 280370, 292008, 559682, 6436344, 6436366, 6436872, 6448510, 6716184, 12872686, 148035890, 148035912, 148036418, 148048056, 148315730, 154472232, 296071778
Offset: 0
T(2,0) = 23^2 + 23^0 = 530.
Table begins:
2;
24, 46;
530, 552, 1058;
12168, 12190, 12696, 24334;
279842, 279864, 280370, 292008, 559682;
...
Sums of two powers of n:
A073423 (0),
A007395 (1),
A173786 (2),
A055235 (3),
A055236 (4),
A055237 (5),
A055257 (6),
A055258 (7),
A055259 (8),
A055260 (9),
A052216 (10),
A073211 (11),
A194887 (12),
A072390 (13),
A055261 (16),
A073213 (17),
A073214 (19).
-
With[{nn=30},Take[Union[Total/@Tuples[23^Range[0,nn],2]],nn]] (* Harvey P. Dale, Oct 16 2017 *)
-
from math import isqrt
def A073215(n): return 23**(a:=(k:=isqrt(m:=n<<1))+(m>k*(k+1))-1)+23**(n-1-(a*(a+1)>>1)) # Chai Wah Wu, Apr 09 2025
Showing 1-4 of 4 results.