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As per your syllabus, the sequence 1, 3, 6, 10, 15, 21,... is called what?

APrime numbers
BSquare numbers
CTriangular numbers (each term is the sum of natural numbers up to that position)
DOdd numbers
Answer & Solution
Correct answer: C. Triangular numbers (each term is the sum of natural numbers up to that position)
As per your syllabus, 1, 3, 6, 10, 15, 21 are triangular numbers (1 = 1, 3 = 1+2, 6 = 1+2+3,...).
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