203203

Appears in sequences

• Decimal expansion of a(n) is given by the first n terms of the periodic sequence with initial period 2,0,3.at n=5A037624
• Triangular numbers containing 2k digits in which the sum of the first k digits = that of the rest.at n=16A068898
• Triangular numbers containing 2n digits obtained by duplicating the first n digits; i.e., triangular numbers in A020338.at n=4A068899
• Triangular numbers obtained as a concatenation of successive terms of A081847.at n=19A082235
• Triangular numbers in which the sum of the external digits equals the sum of the internal digits.at n=30A088289
• Triangular numbers composed of digits {0,2,3}.at n=4A119049
• a(n) = larger member of n-th pair of distinct, positive, triangular numbers whose sum and difference are also triangular numbers.at n=12A185128
• Triangular numbers n such that each decimal digit of n is equal to the difference of at least two other digits of n.at n=21A255917
• First of three consecutive triangular numbers that add up to a perfect square.at n=5A319588
• Positions of 3's in A347381.at n=28A347393
• Odd numbers k such that k/(1+A347381(k)) obtains record values, where A347381 gives the distance from n to the nearest common ancestor of n and sigma(n) in the Doudna-tree.at n=35A386423