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Katydid sequence

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157: 55: + 7 (in any order). For instance, applying the first operation to 1 produces the number 4, and applying the second operation to 4 produces the number 35, both of which are in the sequence. 71:
Pickover asked whether there exist numbers that can be reached by more than one sequence of operations. The answer is yes. For instance, 1814526 can be reached by the two sequences
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A Katydid sequence is the smallest sequence of integers that can be reached from 1 by a sequence of the two operations
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1, 14, 30, 62, 441, 884, 1770, 3542, 7086, 14174, 28350, 56702, 113406, 226814, 453630, 907262, 1814526
28: 106: 100: 24: 168: 131:"Sequence A060031 (Katydid sequence: closed under n -> 2n + 2 and 7n + 7)" 211: 164: 156: 126: 73:
1, 4, 10, 22, 46, 329, 660, 4627, 9256, 18514, 37030, 259217, 1814526
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Wonders of Numbers: Adventures in Mathematics, Mind, and Meaning
130: 172: 192: 8: 58:The first 10 elements of the sequence are: 199: 185: 137:On-Line Encyclopedia of Integer Sequences 105:. Oxford University Press. p. 330. 88: 62:1, 4, 10, 14, 22, 30, 35, 46, 62, 72. 7: 153: 151: 94: 92: 14: 155: 99:Pickover, Clifford A. (2001). 1: 171:. You can help Knowledge by 27:of numbers first defined in 239: 150: 127:Sloane, N. J. A. 167:-related article is a 51: + 2 and 7 29:Clifford A. Pickover 223:Number theory stubs 16:Sequence of numbers 140:. OEIS Foundation. 33:Wonders of Numbers 218:Integer sequences 180: 179: 230: 201: 194: 187: 159: 152: 142: 141: 123: 117: 116: 96: 21:Katydid sequence 238: 237: 233: 232: 231: 229: 228: 227: 208: 207: 206: 205: 148: 146: 145: 125: 124: 120: 113: 98: 97: 90: 85: 69: 41: 17: 12: 11: 5: 236: 234: 226: 225: 220: 210: 209: 204: 203: 196: 189: 181: 178: 177: 160: 144: 143: 118: 111: 87: 86: 84: 81: 68: 65: 64: 63: 47: ↦ 2 40: 37: 15: 13: 10: 9: 6: 4: 3: 2: 235: 224: 221: 219: 216: 215: 213: 202: 197: 195: 190: 188: 183: 182: 176: 174: 170: 166: 165:number theory 161: 158: 154: 149: 139: 138: 132: 128: 122: 119: 114: 112:9780195348002 108: 104: 103: 95: 93: 89: 82: 80: 78: 74: 66: 61: 60: 59: 56: 54: 50: 46: 38: 36: 34: 30: 26: 22: 173:expanding it 162: 147: 134: 121: 101: 76: 72: 70: 57: 52: 48: 44: 42: 32: 20: 18: 67:Repetitions 39:Description 212:Categories 83:References 35:(2001). 31:'s book 25:sequence 129:(ed.). 109:  163:This 23:is a 169:stub 135:The 107:ISBN 75:and 19:The 214:: 133:. 91:^ 79:. 200:e 193:t 186:v 175:. 115:. 53:n 49:n 45:n

Index

sequence
Clifford A. Pickover


Wonders of Numbers: Adventures in Mathematics, Mind, and Meaning
ISBN
9780195348002
Sloane, N. J. A.
"Sequence A060031 (Katydid sequence: closed under n -> 2n + 2 and 7n + 7)"
On-Line Encyclopedia of Integer Sequences
Stub icon
number theory
stub
expanding it
v
t
e
Categories
Integer sequences
Number theory stubs

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