A036526
Smallest triangular number containing exactly n 9's.
Original entry on oeis.org
91, 990, 199396, 998991, 399949903, 2919969990, 39999939903, 999999911791, 9999192996990, 499798990999990, 99597939989199996, 999699998689998991, 19699899919999499091, 999532899999499099996, 999999859999976929990, 199793999409939999989991, 138999999499599999199995, 99996999694999999299662991
Offset: 1
-
nsmall = Table[Infinity, 20];
For[i = 0, i <= 10^6, i++, p = PolygonalNumber[i];
n0 = Count[IntegerDigits[p], 9];
If[nsmall[[n0]] > p, nsmall[[n0]] = p]];
ReplaceAll[nsmall, Infinity -> "?"] (* Robert Price, Mar 22 2020 *)
A048363
a(n) is the index of the smallest triangular number containing exactly n 8's.
Original entry on oeis.org
7, 87, 312, 1287, 10572, 81103, 397212, 881912, 5270652, 7601169, 134021535, 421518419, 1402775027, 4204494972, 42305694389, 397212509427, 1943649189427, 6130065071251, 76024844477168, 98844816642745, 1333325833012312, 6069248534849827, 13303299356842428, 191199837283345112, 1084811955030810572
Offset: 1
Cf.
A036525,
A048353,
A048355,
A048356,
A048357,
A048358,
A048359,
A048360,
A048361,
A048362,
A048364,
A048545.
-
nsmall = Table[Infinity, 20];
For[i = 0, i <= 10^6, i++, p = PolygonalNumber[i];
n0 = Count[IntegerDigits[p], 8];
If[nsmall[[n0]] > i, nsmall[[n0]] = i]];
ReplaceAll[nsmall, Infinity -> "?"] (* Robert Price, Mar 22 2020 *)
Showing 1-2 of 2 results.