6, 10, 14, 34, 66, 130, 258

More Questions from Number Series

• Number series – Find the wrong number (multiply by n then add n) 3, 4, 10, 32, 136, 685, 4116 Exactly one term is incorrect. The intended rule is a(n) = a(n−1)*n + n (with n = 1, 2, 3, …). Identify the wrong number.
• 380, 188, 92, 48, 20, 8, 2
• 4, 10, 22, 46, 96, 190, 382
• Wrong Term in the Fibonacci-Sum Style Series: 13, 14, 27, 45, 68, 109, 177 — exactly one term is incorrect. Identify the wrong term and justify your choice by revealing the intended rule (each term should be the sum of the previous two).
• Wrong Term in the Prime-Square Series: 529, 841, 961, 1296, 1681, 1849, 2209 — identify the term that breaks the pattern (squares of consecutive odd primes).
• Wrong Term in the Fibonacci-Sum Style Series: 1, 3, 4, 7, 11, 18, 27, 47 — exactly one term is incorrect. Identify it and explain the intended rule (sum of previous two).
• Wrong Term in the Cubic-Difference Series: 2, 3, 11, 38, 102, 229, 443 — one term breaks the pattern where successive differences should be 1^3, 2^3, 3^3, 4^3, 5^3, 6^3.
• Wrong Term at the Tail of a Fibonacci-like Increment Series: 2, 3, 5, 8, 14, 23, 41, 69 — find the lone wrong term by analyzing the intended pattern of cumulative increments.
• Wrong Term in the Alternating ×2.5 and ×2 Series (with one error): 3, 7.5, 15, 37.5, 75, 167.5, 375 — identify the lone incorrect term.
• Wrong Term in a Halving-Difference Series: 36, 20, 12, 8, 6, 5.5, 4.5 — find the single term that breaks the “subtract half the previous difference” rule.

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